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Rooftop solar is now cheaper than the grid in 42 American cities (utilitydive.com)
218 points by diafygi on Jan 26, 2015 | hide | past | web | favorite | 183 comments

Solar is cheaper because of you suckers that don't have panels. There is a good government subsidy up front which people know about but the real secret is green energy credits. The green energy credits that the power companies are required to buy from home owners are worth at least as much as the electricity. If it wernt for these incentives then more efficient things like solar hot water would win out, but instead I put a PV array on my roof. When I got my panels the anticipated payback period was just 5 years in Massachusetts.

There is also an implicit government subsidy on coal and gas plants: Not charging them for the externalities they produce namely carbon, mercury, and the other radioactive isotopes they release into the air (not to mention all the water they heat up in our rivers and streams). There is an explicit government subsidy for nuclear in the form of insurance (private insurers won't touch them).

Furthermore, the energy distributed generation produces during the day is actually more valuable to the grid (daytime electricity is generally more valuable than night time with rate prices being an average).

The energy world is a complex place with plenty of incentives to go around.

While it is true that solar during the day is a bit more valuable, what really matters is what it is displacing. Check out this document from the California grid operator on page 3. http://www.caiso.com/documents/flexibleresourceshelprenewabl...

In 2013, the average load on the electric grid only stayed in a 2 gigawatt band from midnight through 6pm. When there wasn't much deviation, nat gas combined cycle plants (or nuclear, or coal) can run most efficiently. But by 2020, the growth in solar production in the middle of the day will cause dispatachable power plants (nat gas combined cycle along with nat gas turbines) to deal with a change of 13 gigawatts between 4 pm and 8 pm. This is a huge change in a short amount of time. Thank kind of ramping of power plants is not efficient.

Also note in the graph that the highest system demand occurs at about 9pm. That means that solar does not help cover the highest demand. In this situation, solar does not help reduce the amount of power plants and it leads to the increased use of less efficient (and faster acting) power plants. So while solar seems cheap, it leads to other costs if you want to keep the lights on.

That data is from a day in January, in California. That usually means lots of sun and low air conditioning load. In midsummer, the solar peak and the air conditioning peak occur at the same time, which is convenient. Peak load is on summer hot days. So that works out.

From an economic perspective, one solution is to buy home-generated solar power at the current wholesale rate, which changes throughout the day depending on supply and demand. This is usually lower than what consumers pay, although it may be higher during peak periods.

Since we have a natural gas glut right now, this isn't an immediate problem. Gas turbines go up and down in power in tens of seconds. It's an operational inconvenience, not a big problem. Things will get better if the battery guys ever deliver something cost effective at utility scale.

All correct, all down voted for being unfashionably true.

Dumping lots of solar power during the day makes usually efficient power generation inefficient.

When dealing with countries with a majority of coal-generation (like mine), it's even worse because they can't idle a coal plant, so they just keep it spinning and sell the power at a loss. This drives up the cost of the power for other times to subsidise the loss, and makes the overall market distorted. This then makes large scale capital investment for base load stations risky, meaning that grid instability is a given issue for the future.

The hand-wavers will say 'just use grid storage' - but the truth is that this is an order-of-magnitude more expensive than conventional generation.

When the push for design of energy generation stopped being an electrical engineering issue and became a social engineering issue, the seeds of the problem were sown.

The day when extreme cold or extreme heat shuts down a grid because of insufficient conventional generation will be the day people will realise.

Convert your coal fired plants to natural gas fired plants. It can then be idled, and its pollution controls are much easier to implement and maintain. Did I mention its carbon footprint is lower as well?

Right, natural gas is a good alternative. Base load power and cleaner burning.

But that is an entirely different proposition to subsidising purchase and use of solar panels at above-market rates.

> But that is an entirely different proposition to subsidising purchase and use of solar panels at above-market rates.

I don't think I agree. Fossil fuels have been subsidized for over a century. Are you saying you don't believe renewables should be subsidized to get us "over the hump" until they're a lower cost option? Because I would disagree with that.

We have the opportunity to move to energy that is clean, reliable, and unable to be controlled by a small group of people. We shouldn't just be subsiding it; we should be producing wind turbines and solar flat out like the US produced tanks and aircraft on automotive assembly lines during both world wars.

Through out the day electricity demand fluctuates rapidly[1], talking about a 30-50% fluctuation between 6am and 6pm. I really don't understand your post, the need for reactive plants would still be needed (and used) without solar power generation. The limiting factor is to make sure that solar fits within the band between the baseline constant load and dispatch provider power. As long as Solar isn't forcing Nuclear plants (or whatever the baseline is in your area) to ramp, it isn't a big issue. Gas plants will ramp through out the day due to our usage patterns, regardless of solar production. Only way impact this is storage.

I've also seen people argue against solar because it means that plant will have to run at variable temperatures, meaning less efficiency. This is also not true because gas stations usually output around 200MW a piece, and when you have 10s of these plants scattered you can stagger their shutdowns, allowing power plant operates to run efficiently longer.


So, we need more storage on the grid.

Currently, as I understand, practically all residential PV coming online is grid-interactive without battery backup. The power companies actively oppose homeowners installing battery backup systems, because they're concerned about people charging their batteries using cheap power at night, and then selling that power back to the utility during the day. In some cases they have refused to approve PV installations with battery backup for this reason.

As a homeowner, I would find a system with battery backup to be more attractive than one that's useless in a power outage (though, granted, significantly more expensive, depending on capacity). While I understand the utilities' concern, I think there has to be a solution. Doesn't it stand to reason that with all this PV coming online, power prices in the middle of the day should drop, even below nighttime prices? And the prices should be highest on summer evenings? And that such a pricing pattern would supply the correct incentives to owners of PV systems with battery backup?

>Currently, as I understand, practically all residential PV coming online is grid-interactive without battery backup. The power companies actively oppose homeowners installing battery backup systems, because they're concerned about people charging their batteries using cheap power at night, and then selling that power back to the utility during the day.

This is because daytime (especially summer daytime) electricity has a greater profit margin, and power companies demand the right to engage in monopolistic price discrimination.

If power companies charged the same mark-up on electricity at all times of day they wouldn't care if you charged batteries at night and used during the day (and it would probably stop being cost effective, too).

>While I understand the utilities' concern, I think there has to be a solution.

The solution is to treat utilities like utilities again (e.g. nationalize them / regulate more strongly). Privatization and profit seeking behavior in a monopolistic market are responsible for this gross market distortion. They are also the reason why the electric grid won't be upgraded to accommodate solar and wind.

The very fact that there could be somebody out there fighting against green technologies using lobbyists because they are too successful for their liking ought to make every American sick.

And then you're replacing the environmental cost of centralized power stations with the environmental costs of absurd numbers of batteries.

I'd love to see some numbers as to if this would actually be better.

How many of those Chinese factories producing PV panels are being held responsible for 100% of their externalities?


Between 15% and 35% import duty on Chinese solar panels.

I don't know if that covers 100% of their externalities, but I'm sure in terms of "taxes paid for externalities caused" they are WAY ahead of any carbon industries now.

This probably wipes out most subsidies too.

I was simply talking about operating externalities. I haven't spent as much time looking at the construction externalities but my educated guess is that on a per watt of generation capacity, the net out of construction and operation favors PV. Not needing fuel is a huge deal.

Externalities go both ways. If you want to hold PV producers responsible for 100% of their calculated externalities, you end up subsidising them anyway.

Don't forget oil. The U.S. military isn't cheap.

It's actually a misconception that solar power is only competitive with subsidies. In the past, it has absolutely been true, but today solar power can really stand on it's own two legs in terms of LCOE(basically the metric that gives a reasonable cost/watt).

Your example (and the OP's) is from rooftop solar, which is a different market. It's much more expensive than utility scale solar, which is the real winner right now in terms of solar power cost performance. But don't get my wrong, I do strongly support subsidies for solar power, it's benefits are many-fold: less GHG, more energy independence, more money in solar R&D further bringing solar power to grid parity in more and more states and markets.

If you think about it, fossil fuels will fluctuate, but always trend up, they are limited. Solar power will only go down. In a hundred years, I would be surprised if the grid was 100% Solar/Nuclear(fusion power will be only 50 years away, in a hundred years), with geothermal and hydro here and there.

I dislike subsidies for solar; I'd much prefer if we were to tax the things we don't like and let the market take care of the rest. I'm not sure I trust a legislative body composed of people who are very nearly statutorily prohibited from having much expertise in the subject to be able to figure out the best alternative energy source. The market, on the other hand, at least has a fighting chance at getting it right.

As you're no doubt aware, "tax" is a dirty word in the current U.S. political climate, certainly much more so than "subsidy". I suspect that goes a long way towards explaining why we have a number of different subsidies related to renewable energy but not a single carbon tax.

Well I should qualify my statements. I think R&D and one time installation tax credits are great and work. I totally and completely disdain feed-in tariffs. Solar should be able to walk on it's own, but I think it's reasonable to give it a hand up.

I don't believe there is too much confusion in terms of what alternative energy source work or do not. There are, however, plenty of entities pushing forward their interests.

For a quick run-down on the truly viable alternative sources:

Solar power:

* Works, it's sustainable, it will only get better. It has already reached grid parity in many markets, this trend will absolutely not reverse but continue. * Is nowhere near it's optimal efficiency, has tons of room for optimization of both cost efficiency and conversation efficiency (basically reducing the area required to reach a desired power output). * Requires a grid that is built with solar power in mind. Requires baseload generation, of which nuclear and natural gas are the best candidates (assuming the natural gas glut continues on).

Wind Power:

* Works, proven technology. It has reach grid parity in more markets than solar. * Is nearly at the limits of it's theoretical efficiency. There are pretty much only manufacturing cost and economy-of-scale gains to be had here, which I think really hurts wind power's future unless some sort revolutionary change happens in manufacturing process takes place. * Also needs a grid that plays nice with, with baseload assistance.


* Not much to say here, it's capped, very little room to grow. Extremely economically efficient but serious ecological effects.


* See hydro, but will less serious ecological effects.


* Total crapfest. Until such time as we can bio-engineer some plant that turns sunlight directly into petrol or the like, biomass offers a a net gain to carbon emissions, especially in the case of corn. Sorghum/Sugar Cane is more interesting but hasn't panned out as of yet, mostly because of it being picky where it grows (it seems unwise to turn rain forest area into sorghum fields in the name of alternative renewable energy).


* Massive amount of energy in a small form factor. * Potential for very bad accidents. (see: black swan event) * Nuclear proliferation concerns, nuclear waste to manage. * Decent economic efficiency. * Nuclear has a niche but can hardly be the world's power source. Would you want every country to be full of nuclear plants, including those whose governments change monthly, are prone to extreme corruption, etc. There are plenty of trade groups they are lobbying for support of "safe" nuclear technologies such as Thorium based breeder reactors, but the truth is these designs are almost entirely vaporwear, and have faults and dangers of their own.

I feel rather strongly the solar is the way forward, with nuclear in stable well-regulated countries for base load, with natural gas/hydro/wind/geothermal filling in the rest.

So what I'm getting here in a nutshell is: You like solar best (and, full disclosure, I do too), for reasons that largely translate into "It's the best and cheapest." To me that implies that's naturally what the market will select if it's forced to move away from things like coal with a carbon tax.

Meanwhile, me I live in corn country. And yes, biomass is a total crapfest, but it's extremely popular with the legislation around here because a lot of moneyed interests stand to make a whole lot more money by convincing legislators to subsidize it. And it's easy enough for them to complete the deal and sell it to the public by choosing a green color scheme for those "10% ethanol" stickers they put on gas pumps. Witnessing those shenanigans firsthand is what makes me extremely suspicious of any forms of subsidy. Excise taxes certainly aren't manipulation-proof, but they seem to be much more resilient to it than subsidies are.

You know what, upon pondering it further and reading your rather excellent case-in-point from your last post, you have totally convinced me.

Fuck subsidies. I believe solar/Nuclear/fusion(heh) will rule the future with or without them. Subsidies tilt the market to and fro without a care about reality, often supporting the wrong ticket.

That's not the political reality we live in though. You can push for some subsidies and tariffs or push against. There is no mechanism to eliminate all of both, even in one country (let alone all countries).

Which means that if there is a market distorting subsidy to one market that you hate (e.g. coal/fracking at the federal level), often the only way to deal with it is create a subsidy or tariff in another (e.g. solar at the local level) as a counter-distortion.

It's also worth bearing in mind that "fuck all subsidies and tariffs" and "let free markets rule" are ideas pushed by carbon-industry funded think tanks (e.g. CATO) when it serves their agenda, but is swept under the carpet when it doesn't (the only solar panel tariffs CATO complained about was the feed in tariff).

To further your point, it wasn't clear (maybe still isn't) which of solar concentrated and PV was going to be more cost efficient. It's not clear which of wind and PV is more cost efficient. These things change year by year as R&D happens. Why should we re-legislate subsidies every 12 months?

Biofuels are a blight on the world.

Biomass electric generation primary uses wood and crop byproducts (so for electric, it's primarily the left overs of cane and sorghum that are used, not the crop: http://en.wikipedia.org/wiki/Bagasse ). Sugar mills wouldn't power themselves with it if it was a crapfest.

I fail to see what sugar mills have to do with the absolute idiocy of corn based ethanol. I would also be interested in the ratio of sugar mills that actually power themselves versus those that just run off the grid.

My point was that biomass electric generation can (and probably does) make sense regardless of whether corn ethanol makes sense. The rest of your comment is about electric generation, so it seemed reasonable to point out that biomass is viable for electric, especially given your blanket statement that it is a crapfest.

I agree with some of what you're saying, but you left out tidal energy sources which are a factor especially once you consider the preponderance of people that live near coastlines.

Some examples:

Tidal tech here and now:



Near future:



The U.S. Navy has committed to get half of its energy from renewable sources by the year 2020. One element of that strategy will be looking to extract energy from tides, currents and waves:


I also think you failed to mention that nuclear is too expensive. That's why places like France (who have had success with nuclear in the past) are transitioning towards alternative energy (like offshore wind) instead of building new nuclear plants.


More sources of evidence that show why nuclear is too expensive:






- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

We really don't need to build new nuclear plants to transition and we should work to responsibly phase them out over time. Here's results from a Stanford researcher whose study shows the world can be powered by alternative energy in 20-40 years:



Mark Z. Jacobson - Energy Policy


Here's for New York (with more numbers):



Jacobson doesn't just throw numbers around, he makes some very salient points along with strategies as well.

We should also factor in advances in decentralized battery storage that are bound to offset current baseload issues. For example, breakthroughs in graphene production, etc.:


Here in Cali there is no green energy credit market for residential solar, so all I got was the 30% federal tax credit. With that credit my break-even point will be just under 5 years. Without said credit, my break-even point would be just over 7 years, which was still a no-brainer for me.

Note this is personal experience with my cash purchased system, as I'm not a fan of consumer debt. Any time a company makes more money off the 'financial products' they sell than the actual physical products or services they sell, you're probably better off paying cash.

But California has net metering, which is a huge, non sustainable subsidy.

Ad absurdum, consider if everyone purchased enough solar for their household to be net zero. The power companies would not be able to charge anything, but need to maintain the grid and provide power at night, cloudy days etc, with capital costs mostly the same as with 24x7 generation.

There's no way power companies would agree to net metering in a free market, so any calculations about the relative cost of solar based on its existence are flawed. It's essentially a calculation of the cost of solar when unlimited battery capacity is provided for free.

That doesn't necessarily mean such a policy is bad; artificially lowering the cost of solar increases production, and increased R&D and economies of scale should make the true break even point come sooner.

But net metering absolutely will need to be wound back eventually - most likely by grandfathering in those that already have their panels, because nobody wants to piss off a bunch of middle class voters by suddenly making their investments underwater.

> Ad absurdum, consider if everyone purchased enough solar for their household to be net zero. The power companies would not be able to charge anything

Untrue. Electric utility tariffs in California include both "Energy Rates" ($ per kWh in multiple tiers based on multiples of baseline monthly kWh usage) and "Minimum Charge Rates" ($ per meter per day, irrespective of usage).

With net zero usage, only the Minimum Charge Rate could be collected. But, given the way tariff setting works, if net zero was common, the Minimum Charge Rate would be much higher than it is now, to cover infrastructure, etc. costs.

The system also includes "standby reservation charges" for energy customers that are also energy generators, but small solar and some other generation systems that aren't selling energy as a primary function and are exporting only "incidental" amounts back into the grid are exempted from those charges under, e.g., PG&E's current tariff schedule. That limited exemption is more defensible as an unsustainable subsidy to small solar (and some other) generators than the basic net zero arrangement is.

I think you're missing my point; if everyone went net zero, and the minimum charge rate increased to compensate, the current payback calculations of solar will go out the window.

If everyone were to buy solar (ignoring production issues) at today's price and technology, the seven year payback rate of the OP would not hold. That's why it is unsustainable.

I think it's unlikely that net metering will be maintained with an increase in fixed rates; eventually the price of power at peak solar will be negative, and it makes no sense to credit households for feeding even more in.

Residents building useless solar panels, overproducing at peak so they can charge their Teslas for free at night, and power companies building massive resistors to burn that power of during the day and coal plants for the night is Kafkaesque.

The right thing to do (long term) is to treat those feeding power back into the grid as commercial customers/producers, where they're compensated and charged based on current market rates. Anything else distorts the incentives significantly.

Edit: And this isn't some pie in the sky theoretical situation I'm talking about - South Australia has already experienced negative power prices at times due to solar, see


> The right thing to do (long term) is to treat those feeding power back into the grid as commercial customers/producers, where they're compensated and charged based on current market rates. Anything else distorts the incentives significantly.

Yes. As pleased as I am to see solar taking off, I see net metering as an incentive to build the industry and bring prices down -- which it is doing -- but one that has to come to an end at some point, maybe not too far in the future.

>But California has net metering, which is a huge, non sustainable subsidy.

Net metering can be a subsidy, but the act of paying for power is not inherently a subsidy, and should continue. There is no reason why people who generate power should not be paid market rate for it.

>Ad absurdum, consider if everyone purchased enough solar for their household to be net zero. The power companies would not be able to charge anything, but need to maintain the grid and provide power at night, cloudy days etc, with capital costs mostly the same as with 24x7 generation.

You're right, this is absurd. You've just declared power generation to be a cost free exercise.

>There's no way power companies would agree to net metering in a free market

I think it's absolutely hilarious that you can un-ironically use the phrase "free market" in the context of defending monopolistic power companies.

The reason why power companies don't agree to net metering is precisely BECAUSE it's the furthest possible thing from a free market (monopoly on infrastructure) and they don't like pesky competition.

> Net metering can be a subsidy, but the act of paying for power is not inherently a subsidy, and should continue. There is no reason why people who generate power should not be paid market rate for it.

I'm happy to talk about this, but you just seem to be looking for straw men to knock down, and are in this thread to push an agenda. My other post, made hours before your reply, says:

"The right thing to do (long term) is to treat those feeding power back into the grid as commercial customers/producers, where they're compensated and charged based on current market rates. Anything else distorts the incentives significantly"

i.e. my position is the exact opposite to what you're claiming, and agrees with your rebuttal to a point I never made.

> You're right, this is absurd. You've just declared power generation to be a cost free exercise.

No, net metering does that (more specifically, grid maintenance, and backup power generation). Which is my point.

Ok, so position #1:

>"The right thing to do (long term) is to treat those feeding power back into the grid as commercial customers/producers, where they're compensated and charged based on current market rates. Anything else distorts the incentives significantly"

i.e. net metering.

Position #2, which contradicts position #1.

>There's no way power companies would agree to net metering in a free market

>my position is the exact opposite to what you're claiming,

Correct. Also the exact opposite of what you claimed elsewhere.

>with your rebuttal to a point I never made.

"There's no way power companies would agree to net metering in a free market" = a point you made.

If your point was actually that net metering should not be a vehicle to deliver subsidies... well, you probably should have been more clear about your point, and if so, should be discussed only in the context of other subsidies and tariffs (e.g. heavy coal and natgas subsidies).

The California Solar Initiative is still active and while Pacific Gas & Electric has exhausted its rebate funds, other utilities have not:


There are plenty of other incentives and subsidies as well (http://www.cpuc.ca.gov/PUC/energy/solar) including writing off equipment costs against property taxes (http://www.dsireusa.org/incentives/incentive.cfm).

The significant thing that is making solar installations attractive to consumers currently are the many zero down options including leasing and lease to own on a lien against your house.

It's growing! I'm personally working on sales software to reduce customer acquisition cost. The bottleneck in the future is going to be order fulfillment.

edit: formatting, new here..didn't know anchor tags are disallowed

Who was your provider/installer? Were you satisfied with them?

I'd like someone here to mount a moral case for why driving up the price for regular users of power to subsidise solar panels is acceptable?

Would anyone accept that increasing gas taxes to give Tesla owners a cash payment is an ethical proposition?

The people most affected by increased electricity prices are the poor. These are the people most unlikely to have solar panels.

I'm all for allowing people to put their money into whatever they want. I am against subsidies for solar or any other energy, when those subsidies are paid for by the other users. It is very unfair on low income households.

Until we stop subsidizing coal, oil, and gas through direct subsidy, tax breaks, extremely expensive wars and ignoring the effects of pollutants, subsidizing renewables is the only way to make it fair.

I am absolutely for removing all subsidies for all forms because I am confident that solar presents a much better value. But ask a politician to suddenly start charging fossil fuel users for our wars and pollution and they'll instantly pull out the line that "raising prices hurts the poor".

So subsidizing solar is just more politically feasible. It is certainly not the best solution but reversing a 100 year old industry is basically not going to happen. So if we don't want solar to be at a disadvantage (which would strike me as immoral given the value it offers) we basically have to subsidize it.

But soon, unsubsidized solar will be cheaper than our indirectly subsidized fossil fuels. The raw panels already only cost $4000 or so for a 5kw home system, and great effort is underway to reduce the cost of installation and inverters.

It is unfair to ask non-fossil fuel users to live in a world polluted by fossil fuels, but nobody ever asked us about that one.

>But soon, unsubsidized solar will be cheaper than our indirectly subsidized fossil fuels

It kind of already is, which is why the fossil fuel industry panicked and got Obama to slap tariffs on cheap Chinese solar panels.

Would anyone accept that increasing gas taxes to give Tesla owners a cash payment is an ethical proposition?

Yes, I would accept that. In fact if you consider that we are giving Tesla owners a cash payment when they buy the car, a lot of people accept that proposition.

I'm not sure why you think that the people most affected by the increase in electricity prices are the poor. Sure, poor people are more susceptible to all price increases, but is electricity worse than food? Or even gas? Note that your electricity bill is heavily dependent on the size of your house. My current electricity bill, all in, is $50 a month. I live in a 1 BR in NYC. Back when I had a 3BR condo in CT, it was $150-$350 a month. The size of the house factors in a lot. I imagine most poor people don't have bedrooms to spare that they spend a bunch of money air conditioning in the summer.

I do know that many low income areas are right next to highways, and that pollution from gasoline powered cars impacts the health in those areas greatly.

So if you want to talk about ethics, I think it is very ethically appealing to incentivize people to reduce emissions that are likely harming people near highways a lot more than a slight increase in electrical bills or gas taxes.

Poor people are often subject to fuel poverty, especially in regions with cold winters. This is established fact, and it's shocking in a world where power can be abundantly generated and distributed that poor people suffer and even die as a result.

The cash payments for Teslas are just wrong. Subsidising the purchase of wealthy peoples cars using taxpayer money is indefensible IMO.

If I change the vehicle from a Tesla to a turbo diesel BmW SUV, is it still ethical? The X5 has lower emissions as well.

It's absolutely stupid to argue that we can only subsidize fuel poverty OR electric cars while we spend a trillion dollars on evil wars and another trillion dollars on subsidizing a parasitic banking system.

Added to which, subsidies are how almost all countries build up their industries which provide jobs and wealth for all. China didn't get rich by letting its currency float and letting free markets reign.

>The people most affected by increased electricity prices are the poor.

If you want to see where solar panels have really taken off, you should pay a visit to the third world where the US government isn't subsidizing them.

Demand for solar panels may be higher in some of the third world communities since it is one of the few sources of electricity; there aren't too many grids to connect to.

Point being that it's one of the few power sources that ARE available to poor people, especially poor people who are not on the grid.

It's pretty much just that and diesel generator, in fact.

And if you asked those people, they'd probably prefer a regular grid so they could use power at night, when domestic consumption is highest.

You should check out California. It's one of the world's largest solar markets, and it has really taken off there.

And Hawaii has taken off even more than California. It thrives wherever electricity is overpriced and there's enough sun.

Here's a potential argument.

Global climate change impacts the poor the harshest. They're the least able to cope with it, and can least afford the long-term impact economically and to their food supply.

The subsidies to solar assist in building out the long-term technology/energy innovation and infrastructure necessary to combat climate change. Those investments must be made, because we're not going to just magically wake up one day with extremely effective solar, we have to build our way there gradually through university science, commercial R&D and product deployment.

I'd argue that the wealthier people buying these panels are paying their fair share of the overall cost when it comes making the energy shift possible, and were even more so in decades past when it was far more expensive and far less efficient. The top 20% pay something around 70% of all income taxes; the bottom ~15% have a negative tax basis; so the wealthy are largely funding the tax credits that they're claiming anyway.

The contribution the poor are making in very slightly higher electricity rates, is their fair share of contribution to the solution of climate change. No different than any other product build out in history, in which the rich subsidize most of the expense of new technology, but poorer consumers also have a role to play as prices come down.

It's also worth noting that in the US at least, the poor often have subsidized utilities. It's the middle class that is actually taking the bulk of the cost hit you're referring to, not the poor.

If you are stating that current poverty should be made worse so that the currently ineffectual emissions reductions through the use of solar panels might benefit their grandchildren by changing the arrival date of spring by one day, then that's a completely bankrupt argument.

'Very slightly higher electricity rates', 'fair share of contribution to solution of climate change'

The fact is, household solar panels has - rounded off to the nearest whole number - 0% changed the amount of co2 emitted in countries like the United States. This is because there has been no change in gas or coal power generation as a result of solar panels. The entire contribution of solar is still less than 1%.

Meanwhile the UK government started collecting statistics on fuel poverty and some areas had 15% fuel poverty - mainly in unemployed households in rented accommodation. This number has doubled since 2005, when 'fight global warming' policies by interfering in the energy market became popular and energy prices have doubled or more.

It's incomprehensible to me that anyone can say 'pay more, suckers, I got mine!' when we are talking about energy for people to keep their homes habitable. And all this for an ineffective response to a far-off problem.

I cannot fathom the popularity of such thinking, when the same people, if presented with any other taxation or cost increase on poor people to subsidise consumption of rich people - would say that it is unthinkable.

It takes 'suffer in silence, it's for your own good' thinking too far.

>If you are stating that current poverty should be made worse

NOBODY is suggesting that.

If you want to fix poverty in the United States, there are several very straightforward ways of doing this - bolstering SNAP, extending medicare, raising the minimum wage, building social housing and creating a job guarantee (as was done during the last depression).

These are, incidentally, all things that anti-solar groups like ALEC are also usually against.

Added to which, solar panels are actually the only form of power generation which is within the reach of poor people, which is why millions of people in the third world are taking advantage of it. Give 0% credit for it (as is available to all big banks in the US to play their gambling games) and literally everybody would be rich enough to take advantage of it.

But if you are increasing energy prices for things like solar subsidies, then you are making poverty worse. There is no avoiding that.

I'm not going to comment on all your other suggestions - that's not the point I want to make. That point is - making poor people pay more for electricity so that rich people can get a rebate is just wrong. There is no justification for it. To fix things, first you have to stop making them worse.

Please point out where I said, or even hinted at, anything like this:

"If you are stating that current poverty should be made worse ... "

Raising electricity prices a fraction of a percent on poor people who are already receiving subsidized utilities, is not making their poverty worse. As you noted, solar isn't widespread, and thus is obviously not raising electricity prices in a meaningful way.

The price of coal moving up or down 1% does more to impact the price a poor person pays for electricity than all of the solar tax credits in the first world combined.

It's clear that the poor in the US are not going to pay a lot more for energy. They're going to receive higher subsidies from the welfare state to compensate for any price increases. Given the poor are already running a negative tax basis, it's accurate to say they're not paying for electricity at all to begin with. And to make this point easily clear: show me the negative tax basis of the average poor person in the US, and then show me the average poor person's electricity bill.

If one actually cared about the poor and their electricity bill, the only meaningful place to start is the Federal Reserve, putting an end to their 40 year debasement of the US dollar and this chart that it has caused:


Your right, I misread your original comment. However, supporting subsidies for solar through increased prices for everything else does penalise the poor.

We are in agreement about the Fed. Only the debasement goes back further than 40 years - that was merely the acceleration point.

You do know that PPA rooftop solar is zero $ upfront & cheaper than 'normal' electricity, right? Nothing stopping the poor from getting it. In fact, I would be very surprised to hear that PPA customers average income is lower than in the general population.

Fossil fuels would be more expensive if someone had to pay what it would take to capture and store the pollution.

The same could be said for many things. Cars, plastics, cattle, factories, pesticides, airplanes, etc. Why are fossil fuels special?

Isn't that assuming that people live in a state with an SREC market? In Missouri where there isn't an open market for SRECs my utility company offered to buy my credits for a puny $5 per which is down from above $20 per a few years ago.

In my understanding, it isn't the state that matters, but rather the type of firm that sells you power. If e.g. you have Ameren UE or another investor-owned corporation, they are required to pay something like the going rate for your excess power. However, if you're with a co-op like Laclede Electric, they aren't required to pay more than a small fraction of the price, and even then under onerous conditions like only giving you credits that expire within a year.

That isn't to say I'm a fan of Ameren. They get up to their own shenanigans, just not these particular shenanigans. I suspect the reason they don't care about this is that it's a perfectly PUC-acceptable reason to raise rates for everyone else. At a co-op with voting members, however, that maneuver isn't so easy.

SRECs are completely different and separate from net-metering or electricity purchasing requirements. In states with an SREC, you can sell renewable energy credits to clearing houses or companies who use those credits to cancel out non-green practices (like buying carbon offsets from Al Gore).

Solar is cheaper because of you suckers that don't have panels.

Surely the economics of the situation dictate that if everyone who didn't have panels had panels, it would be even cheaper, given we are not going to run out of silicon.

The argument is that customers of the power company are funding payments to owners of solar panels.

If there are less/no customers of the power company, there aren't as much/any funds for those payments.

Also, you can't have these solar panels without the power companies. The solar panels only produce electricity while the sun is up so the people with solar panels are essentially using the utilities as free batteries - produce power during the height of the day when less power is needed and use more power ~5pm when the grid is at its max.

Power is almost always more expensive in the middle of the day. You can see this if you look at the energy component of the hourly electricity price (day ahead or real time) for any of the organized electricity markets (though you aren't totally wrong, the winter load profile does have a local minimum 14-17). Residential use lags in the midday but commercial + residential almost always peaks midday. In other words, solar generation occurs closer to peak pricing (i.e. solar electricity is more valuable electricity).

Also, you can't have these solar panels without the power companies.

Not true any more, not that it ever really was, is just a lot cheaper to do now - http://www.aquionenergy.com/

If there are less customers of the power company, then the electricity per person is more expensive and solar is then even more competitive. This prediction for the collapse of conventional electricity suppliers is being referred to as the solar-death-spiral and it came from wall street, not the green lobby.

Batteries have huge economies of scale, and solar needs them.

The utilities will change, but I doubt they'll disappear.

True enough, but the initial comment from chrisBob was about the immediate situation.

But those same customers have for decades funded the capital expenditure of the power companies without getting to own anything at all. If they take their money elsewhere you can hardly blame them. It is like getting a mortgage instead of renting.

In the country where I live no one does solar. The reason is that it doesn't get heavy subsidies, and the utilities have dropped their prices to discourage competitors from entering the market. We also screwed up the feed-in tariff system. So, you can drive around local cities for hours and not see one single panel.

That might actually be good in the long run. Part of the actual cost is the maintenance, and installation. Most of the solar power fanatics fail to count all the costs in their calculation. With a large scale utility those things are all in.

At least with Solar City, installation and 30 years of maintenance are included in the cost of the system.

I don't really think that is accurate? It is my understanding the work of installation is under warranty for 30 years. This covers roof leaks, etc.

There is not really much to maintain in a standard residential solar installation as there are no moving parts. Except for the panels. They need to be kept clear of debris, dust, shade, snow (depending on geography).

It is my understanding that SolarCity does NOT maintain the surfaces. They will let you know of current degradation or fluctuations but it's up to you to debug / clear the problem.

In places with non-optimal solar climate I imagine that clearing the snow will be a pretty labor intensive job?

No, and there is a financial proof: you can get a PPA deal. If the snow makes the output lower you just don't pay anything and the company losses. So we can assume that either the snow just falls off or that they would come clean it.

It is interesting that Hawaii isn't at all mentioned, considering that electricity is 30 to 45 cents per kWh and the electric company limits the number of grid-tied solar installations per neighborhood.

No where in the US is solar more cost effective than here, and the electric company is restricting homes from installing solar. The alternative is to go fully off-grid with battery arrays, but that is more than most people can handle.


It's not as sinister as it sounds. You have to upgrade capacity to handle the power produced by neighborhood capacity or you burn out the lines.

Not that they have to go fully off the grid all the time, just when they want to use solar.

Packaged right, this could give electric cars a big push. A Nissan Leaf sports a 26kW/h battery; a rough guess puts the cost of a home solar charging system dedicated to the car at about half the price of that car. For context: charging it from 110v is like running a moderate hairdryer for the charging period (up to 21 hours for a full charge, which is unlikely needed).

Packaged right, this could get a big push for dedicated A/C operation. Home cooling being most needed when sunlight is strongest, solar could significantly reduce or outright replace the considerable power needed for cooling - and do it with a minimum, if any, battery buffer.

One of the most important attributes of solar power is that it produces peak power during peak usage times -- the middle of the day, when people are running the air conditioning, businesses are open, computers are on, and so on. With a grid designed to provide continuous power at off-peak levels and solar filling in for some of the shortfall at peak levels, that allows a reduced number of peak-only reactors.

An earlier post linked to a California operator's report: http://www.caiso.com/documents/flexibleresourceshelprenewabl...

...that shows peak load is actually 6pm-9pm.

From the report, just before the graph -- "The net load is calculated by taking the forecasted load and subtracting the forecasted electricity production from variable generation resources, wind and solar"

In other words, after projected solar generation is accounted for, the peak remaining power need for the specific grid in question is at 6-9 pm. (Other parts of the paper describe the "belly of the duck" being caused by "supply from solar generation resources" -- reducing the need for the rest of the grid to supply daytime power.) The paper in question may also be describing a residential-only grid.

Residential peak usage is from 6-9 pm, but when commercial/industrial power usage is accounted for, the peak is more like 2-6 pm. See the chart at around the 2/3 point of http://www.mpoweruk.com/electricity_demand.htm . Also note that residential demand may peak earlier on super hot / high sun days, as shown at http://blog.opower.com/2012/09/hot-and-heavy-energy-usage-ho... , and tends to peak later in the winter due to electric heaters kicking on in the evenings (https://www.gov.uk/government/uploads/system/uploads/attachm... ).

Of course, I'm glossing over a lot of complexity here. Each region is going to be different depending on a lot of factors. But in general, having a decent amount of solar power generation can help meet demand at the peak of commercial/industrial demand.

ah, thanks for explaining the details!

This is Nick Carr's "The Big Switch" in reverse as I predicted years ago. It used to be the case that centralized distribution was cheaper, than, as described in the book, every factory having its own water wheel power plant. The technology is getting good enough now though that each endpoint can be self-sustaining, and even provide services - just as the internet should be - every endpoint providing and consuming. This trend will be massively disruptive, and expect centralized services to do just about anything they have to, to protect their dinosaur business model.

Having had solar panels on my roof for nearly 15 years now I can tell you that the 25 year warranty is optimistic at best. Our panel maker, Sharp, cannot replace panels under warranty (180W) because they no longer make them and have no replacement stock. We discovered this when we tried to exercise the warranty on a panel that failed.

As with any warrantied product there are likely provisions for that in the warranty - you should either get cash value compensation from them or an equivalent modern panel.

Just because your first attempt resulted in a 'no' doesn't mean you are without recourse...

Oh they were happy to replace my 180W panel with a 165W panel, but at the time such systems (like mine) are built as 'strings' of panels in series. So putting a 165W panel in took all of the other panels down to 165W (which in my case effectively removed one panel equivalent). The higher wattage panel was too large for the roof mount. We ended up replacing the panel with a Chinese equivalent (which was 180W and the right panel size) and basically threatened to sue Sharp for the panel cost. (which they ended up paying).

You have to be careful to match the panels though - slightly different specs can cause problems for your setup. The same goes for batteries - mixing new and old will degrade your new batteries. (Lead acid batteries at least)

Sure, but in the long run it is far better to take the new panels and tweak your system.

I believe this is the development that will let us avoid run away catastrophic warming.

In order to avoid catastrophic warming we have to reduce emissions by something like 80% by 2050. That seemed a pipe dream before cheap solar panels, now it feels inevitable to me.

70% of the power generated by a coal plant is wasted in the transmission line before it reaches your home, distributed generation has this huge efficiency benefit going for it.

The Chinese solar industry has gotten the price down below .50 per watt this year, in a few years it won't make sense to add carbon-sourced marginal capacity. Almost all of new demand can be satisfied with solar pv. We will have to solve the energy storage problem, and I think we will. Superconducting magnetic energy storage gives me hope.


>70% of the power generated by a coal plant is wasted in the transmission line before it reaches your home

...that sounds like an order of magnitude too high. Here's couples of sites that claims that the number is 6%-7%.



I think the 70% number includes inefficiencies associated with the generation cycle. A coal plant efficiency is around 35-40% subtract off transmission losses and you are close.

70% wasted in the transmission line, eh? Where did you get that number?


Probably confusion with the thermal efficiency (which Wikipedia says is ~33% for coal).

Just for context, solar provides <1% of world electricity and nuclear provides >10%, both of which produce very little CO2

I can install solar on my roof in 1-2 days (after permitting/approval). I cannot install a nuclear reactor on my roof.

They've become smaller and more maintanence-free than you might expect. http://en.wikipedia.org/wiki/Small_modular_reactor

I don't doubt that, and they're probably very valuable in locations that don't get a significant amount of sunlight (near the poles), but I can walk into Costco and pick up enough solar panels to power my house.

What's the purpose of stating the obvious here?

My interpretation of the post I responded to was that solar and nuclear are both carbon neutral energy sources, but that somehow nuclear was "better" because it provided 10x as much power globally. My post was to articulate that solar can be deployed anywhere, much more rapidly, and is therefore the better choice.

Thanks for calling me out on it!

Not yet!

that's 1% and growing, 10% and shrinking.

A lot of research has gone into flywheels over the last 40 years or so. The best that came out of that was ride-trough systems for hospitals and other large consumers (datacenters!) which catch the load until the generators can be spun up and power stabilization for wind parks (but these have now been supplanted by more solid state tech using superconductors).

There are all kinds of reasons for that much too involved to go into here but for most practical (and cost efficient) applications fly-wheels are probably not going to happen unless there is a breakthrough in materials that would allow much higher RPM.

Other interesting applications where the gyro bus (http://en.wikipedia.org/wiki/Gyrobus ) and a similar system used to power regular cars (the flywheels were in the 100K+ RPM region and the size of a large dewar flask).

Well, they just don't seem as science fictiony as superconducting batteries. Coal and oil seem like great ways to store energy until you need it. Turning electricity into coal seems pretty tricky though.

If the cost of panels keeps dropping like this, i think a lot more money will go into electricity storage. no idea what that storage system might be though. with home generation, batteries aren't as encumbered by size and weight when compared to a car or a laptop. Maybe some big heavy battery tech will come along and give us a good chemical storage answer.

Maybe in the future, power is generated on rooftops, and large centralized installations store the excess energy till night - replacing some fraction of our current coal/oil/gas/nuke generating capacity.

You missed an easy pun with some outdated lingo. Lemme correct you.


Flywheels are pretty fly yo.

1. 70% loss is incorrect as others have pointed out. 2. What 'catastrophic runaway warming'? The latest IPCC report says 1.5 degrees by 2100. Neither catastrophic nor runaway. That is business as usual scenario, which doesn't factor in the development of new generation methods in the next 80 years, which is a virtual certainty.

There is a 70% loss in generation and transmission. Standard coal plants convert 30-35% of the energy in coal to electricity, ~7% is lost in the lines.


Runaway catastrophic warming is what we will be dealing with if we stay on the business as usual approach: http://rsta.royalsocietypublishing.org/content/371/2001/2012...

I'm basing my argument on the work of Dr. James Hansen from NASA. The IPCC's predictions keep coming back as incorrect, too conservative. The IPCC has had to rewrite their predictions, the situation is proving worse than they thought.

Dr Hansen has had himself arrested for activism so many place little credence in his views, particularly as he likes to contrast his scientific work with exaggeration when talking to the media.

The IPCC predictions have all been revised downward with each report. The only thing that has increased is their 'confidence level' which is not statistical confidence but author confidence.

I don't know what will happen, but I do know that nobody else does, either. Every single simulation so far has been completely off by a factor which makes it worthless.

The only thing we can predict is that better, cheaper forms of energy will be produced, and these are likely to be lower emissions than what we have today. Pricing out lower income people in the present day in the hope of making a difference is morally wrong in thighs is context.

Electricity generation is only a small part of carbon dioxide emissions. If you're worried about global warming, I suggest becoming a vegan.

that's disingenuous - electricity from fossil fuels, along with agriculture and transport are the 3 biggies. it makes more sense to say "yes, but don't forget transport and food". cheap solar and electric transport are pretty closely coupled as well especially if your car(s) can seamlessly act as your battery pack reserve.

Private car transportation is only a small part of transporation.

How would becoming a vegan materially affect carbon dioxide emissions (or more saliently, the ratio of CO2 in the atmosphere).

He's probably referring to methane produced by livestock.


Hmm, but there's lots of livestock that doesn't generate methane (and she/he did specify CO2 there).

Making everyone else become a vegan (or, at least, internalizing the externalities associated with livestock so that market forces would make that a much more common choice), but doing so yourself won't. Classic tragedy of the commons.

I do understand the logic of pro-vegan types on this front, but apart from believing it's fundamentally flawed, I was especially curious on the specificity regarding CO2 in this case.

If the planet's population became vegan, we'd have some serious nutrition and soil management challenges to contend with. Cycling (or part-provisioning of) nutrients without using animals or without using methane and other fossil fuels (think Haber Bosch) is a mystery to me absent animals on the farm.

Here's study on carbon footprint of different diets: http://shrinkthatfootprint.com/food-carbon-footprint-diet

"If the planet's population became vegan, we'd have some serious nutrition and soil management challenges to contend with."

Nope. In addition, the whole world is not becoming vegan at once. If you think that's a problem, become a vegan now so that the whole world is not becoming vegan at once.

I carefully avoided the 'at once' bit. Clearly that would be even more infeasible.

That study / blog post is certainly partisan - but it is written by an energetic vegan (hmm, you'd think that'd be an oxymoron).

I've still yet to see a workable solution to the Nitrogen and Phosphorous (as well as all the other micronutrient and mineral) cycles that does not intrinsically require the involvement of animal husbandry or the input of massive amounts of energy.

Let me throw a reference to a properly researched study back at you - Simon Fairlie's 'Meat: A Benign Extravagance'


Solar is only a piece of the puzzle.

The main issue is that in the US, we use up twice the amount of electricity in the day than we do at night. Spinning up and spinning down the turbines / generators causes enormous amounts of waste.

Green energy can't "spin up" and "spin down" like coal, oil, or nuclear.


Some large percentage of our grid (in particular, the "dynamic" portion) will have to be Coal, Oil, Gas, or Nuclear. The Gigawatts of energy differential between day-usage and night-usage foregoes any hope of storing that energy.

Combined cycle natural gas turbines are extremely easy to throttle compared to baseload like coal or nuclear. Even most diesel/bunker fuel facilities that were used for peaking have been shuttered or switched to natural gas, because of cost as well.

Natural gas turbines are just fine as a peaking stop gap until we have the renewables dispatchability problem solved.

here in NZ (no subsidies in our electricity market) we are about 70% renewable via hydro and geothermal. we run a parallel 'reserves' market (everyone does, it's there to take up the slack of a plant tripping out). typically a hydro plant will run 'tail depressed' which means it's not as efficient as it could be but can scale up within 7 seconds (there's another 7 minute reserve market). prices adjust, people get paid to conserve fuel (water) but it's availalbe when needed. fast start gas turbines are also common but these tend to be at the 10-15 min mark (which is still blistering!). tl;dr 'green' energy _systems_ spin up and spin down just like the regular kind...

Hydro is one of the best "green" energy sources, and we definitely need more of it.

The downside is that rivers of the size that can power a Hydro-dam are relatively rare, and ecological issues (flood zones, and whatnot) need to be taken into account.

So I'll amend my original post with Coal, Oil, Nuclear or Hydro.

Solar and Wind are absolutely terrible at "spin up" and "spin down". So other sources are needed to cover the differential.

My understanding is that it is not practical to turn nuclear on and off to meet demand. Am I just wrong on that? Do you know of a good resource to learn more about this?

It's not practical to turn on and off any steam based power plant.

Coal and nuclear fuel are simply used to boil water. The steam created in both plants is then passed through a steam turbine, which turns a generator. The turbine is finely tuned to a specific set of steam characteristics. These are generally related to temperature and pressure. The process of getting the steam loop up to the right temperature and pressure takes a significant amount of time and energy. Once it is at steady state, it is very efficient.

Natural gas turbines work differently. There is no steam. The natural gas is burnt directly in the turbine, much like a jet engine. Thus you can throttle it just like an airplane. There is some lag, but it is relatively responsive.

The report estimates an inflation rate of 2.7% but the core inflation rate is currently much closer to 1.7%. They therefor underestimated the cost of the loan which will make solar panels more expensive.

But core inflation excludes energy costs..

Energy costs are much lower today. Have you noticed the $2.00 gas signs?

You should not confuse a temporary turf war between tight oil drillers and the Sauds with long-term energy cost inflation.

$2/gal isn't sustainable for anyone except consumers, and it won't last more than a few months.

My thinking is that the Saudi actions right now are more geopolitical than they are aimed at the oil market. I guess the oil market itself is pretty geopolitical, but I see a strong possibility for some anti-Russia, anti-Isis quid pro quo between the US and Saudi Arabia.

(It's win-win for them if they put the pinch on new production, I'm just not sure they are hugely concerned with that)

Oil futures for 2020 are trading at $67/barrel. If you think that's low, maybe you should buy some. If you think that's right, maybe this will last more then a few months.

I stick to equities and food commodities for trading. Trading oil at my scale (<$10MM/year volume) is like walking into a Mos Eisley cantina inebriated and with cash hanging out of your wallet. I'll make you a Long Bet [1] though if you're interested (a beer of your choice if you're right).

[1] http://longbets.org/

I'll give you that point. Although note that Russia, Iran, and ISIS are sanctioned right now, so keep that in mind for the short-term. Supply is BOTH artificially constrained and artificially inflated right now.

But it isn't obvious to me that gas prices should go up or down.


Does this factor in the huge tariffs on panels made in Asia?:


If it doesn't then the picture won't be as nice, but if it does then imagine what the situation could be like.

> but if it does then imagine what the situation could be like.

Depends on how much of the "asian manufacturers are artificially deflating costs through government subsidies in order to buy up global market share, therefore we need tariffs to level the playing field for domestic manufacturers" argument you buy.

Actually, none. If they can provide solar panels for free for the rest of the world let them. That's a subsidy of other governments with as ultimate beneficiary local citizens.

> with as ultimate beneficiary local citizens.

Yep. See the Thiel essay about how the point of business is to acquire a monopoly, at which point you kick back and let the cash flow come in because there's no competition: http://www.wsj.com/articles/peter-thiel-competition-is-for-l...

One theoretical use of tariffs is to sacrifice economic efficiency in the short run to maintain healthy competition in the long run. Don't get me wrong -- tariffs also serve many more interests (protectionism, regulatory capture, etc.), but the there still is a short-term/long-term difference I think you're discounting.

I've got a mix of evergreen and deciduous 30+ meter trees on my lot that produce (eyeballed) about 25% roof shade in winter and about 50% roof shade in summer. For aesthetic reasons, the trees are non-negotiable: they stay (and neighbors' trees provide morning and evening shade; equally non-negotiable). It appears that kills the deal; the linked PDF says my region could expect about $60 worth of power a month without the trees, but with them I'm guessing it would be at best $40 a month, which isn't going to cover a 5% interest cost.

Solar panels would be fantastic at my townhouse in San Jose, where the sun shines 300 days a year.

Unfortunately, my HOA bans rooftop solar panels.

As another poster below said you should work with your HOA to change that. I was in the Board of our HOA (a townhome community), recently decided to step down, and we amended our CC&R to allow solar panels. We had to add a few caveats but no biggie.

You may have already done so, but you may want to see if that restriction is in conflict with CA law: http://solar-rights.com/files/THE_CALIFORNIA_SOLAR_RIGHTS_AC...

The roof of a condo is often considered common area, which is excluded from the linked law.

OTOH, parent can (and should) work with the HOA to get those CC&Rs changed. In the uber-green region that is the valley, it should be pretty easy to get a group of like-minded owners together to approach the board, or even get a member or two elected.

Interesting stuff, but there are financial assumptions being made here that should be examined.

1. The 25-year ROI is tied to the projected price of electricity moving forward. It is simple market issue that if and when more and more people start using these systems, the utility-based kW price will (must) come down and therefore, the ROI will change, perhaps dramatically.

2. What about the opportunity costs of such a significant financial commitment? Have they been examined in any way?

Sunshine. They talk about a 5kW system, but do they use some theoretical cost or do they consider the amount of sunshine in each location. When I see Detroit at #25 I'm suspicious because we have a lot of grey days.

Impressive given how cheap gas is now. Solar has gone down even faster?

petroleum is not a significant fraction of energy on the power grid.


It looks like about 1/3 to me. I would say that is significant. I wonder if the study would have the same conclusion now that oil costs about 1/2 of what it did several months ago.

Natural Gas != Oil. These products might come out of the same well but do not track prices.

All oil based products are less than 1%. Nat Gas is 27%, Coal 39%.

Wow, never would have guessed.

Will new solar panels last 25 years? Most of stuff on the outside on my house doesn't have a lifespan that long. You could end up paying off the loan after the panels have stopped working.

Most are warranteed at a particular percentage of nameplate capacity (95%+) at delivery and then in a straight-line decay after a certain point out to a certain level (75-80%) at 25 years.

http://us.sunpower.com/sites/sunpower/files/media-library/wa... [edit: better link], for example. that is 95% through year 5, then .4% linearly through year 25, or 87% of nameplate at year 25. They are a premium vendor, but the warantee structure is fairly standard across legitimate vendors.

edit: http://www.yinglisolar.com/assets/uploads/warranty/downloads... - 98% at install, 92% at 10 years, and 82% at 25 years.

edit: http://www.trinasolar.com/downloads/us/products/EN_Trina_War... 2.5/3.5% in year 1, 0.7/0.68% through year 25 (80.7/80.18 % at end) for poly/mono- crystalline products, respectively ... and so on.

an upvote is not enough, thank you for a response with hard numbers and multiple linked sources.

Many have guarantees of 20 years. Whether there will be someone around to honor that guarantee is another matter, of course.

Seattle is on the list! I'm pleasantly surprised.

Seattle actually gets a decent amount of insolation compared to Germany: http://www.greenrhinoenergy.com/solar/radiation/images/World...

As we know, Germany isn't shy about its solar investment.

Like most things, making a capital investment results in a cheaper cost than consuming a service.

The problem is, you need to invest $30k to save $50.

Subsidized rooftop solar is now cheaper than artificially expensive electricity in 42 American cities.

Electricity from natural gas costs $0.03-0.05/kWh to produce and deliver.

Anything beyond that is mark up; either profit or regulatory.


Any more references here? It looks like you just mean the price for natural gas futures is $0.03/kWh. I am hesitant to believe that includes production and transport. In addition, are you including the efficiency at which natural gas is converted to electricity?

I'm dividing by 0.3 to account for the efficiency of natural gas turbines. (In reality they're higher at around 35-45%)

If you assume a 100% efficient natural gas plant the cost is $0.00983/kWh (100% efficiency is of course nonsense though).

At 30% efficiency the marginal cost is $0.0327/kWh, distribution usually costs around $0.01-0.02/kWh.

This leads to a grand total margin cost of $0.0427-0.0527/kWh.

DoE estimates from 2012 show $0.0189/kWh in fixed costs.

So a combined grand total of $0.06-0.07/kWh.

Your marginal cost is about what I'm paying for electricity.

What about capital costs?

"DoE estimates from 2012 show $0.0189/kWh in fixed costs."

That includes capital costs.

Fixed costs =/= capital costs.

Fixed costs are the reoccurring costs that arise regardless of production. You can build a plant with free money, but you still have fixed costs.

Sorry I meant to say that the metric I called fixed costs is actually fixed and capital costs.

Fixed costs alone are ~$0.002/kWh...


The US has better housing affordability than pretty much any other developed country:


I'm really not sure you can call the cities at the top of that index "developed". i.e. Detroit.

Those cities have stats that make people from actual developed countries gasp in horror.

To be fair, that's mostly because people on average don't understand statistics.

Fair point.

However, places like Sacramento, Denver, Houston, Austin and other large cities with quite a lot of jobs have great housing affordability compared to most places.

Find the first Australian city....

It gets even more fascinating when you dig deeper.

In Australia, your income covers your healthcare, education, etc. etc.

In that states, you have to pay for that yourself.. so if you take that off "income", you have a good chunk less to spend on a mortgage.

(I'm not saying houses in Australia are anything close to affordable, I'm saying it's much more complex and nuanced than "income vs. mortgage")

In Australia, your income covers your healthcare, education, etc. etc.

You mean the income tax (taken out of your income) pays for healthcare, education, etc, etc?


Given you are pretentious enough to use words like pleb, you may also have the wit to be aware that none of that in any way supports your initial claim.

Given that you are so offended by being called a pleb, I'm sure you won't mind putting solar panels on your new affordable home in less crime ridden areas like Somalia or Sing Sing. Solidarity with the poor for all!

Considering the number of home starts someone is affording them just fine. The age of nearly free money may be past and square feet might be more realistic going forward. The issue is, did people learn the lesson of not getting more mortgage than they can truly afford?

I wonder even more if the banks have learned the lesson of not making loans to people who can't afford them? And whether the banking regulators will have the balls to stop the fraudster when they start demanding fraudulent appraisals from appraisers (as the banks and mortgage brokers did in the bubble years) and making liars loans.

Also note that while housing start have recovered since the low post-crash, they are still at historically low levels in the US. See http://3.bp.blogspot.com/-0kkME86BGHc/VL-qoysEIbI/AAAAAAAAiB...

There's two sides to that story: have we put regulations into place that prevent another sub-prime mortgage crisis? Or, are those regulations going to fizzle out in the next administration?

the regulations are meaningless with the current state of regulatory capture. The Democratic and Republican parties in the united states appear to be united together in this corruption.

With a 25-year 5% loan, I can afford lots of things!

Hello from the UK. Average house price here is now around 380,000 US dollars, compared to around 190,000 dollars in the USA. And we have the smallest house sizes by floor space in Europe.

And we have both a lower median income and lower incomes towards the top end. :(

Don't feed the troll.

... not counting storage, but it's progress.

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