I signed up for such "brief" interruptions with our local power company when it first rolled out. A few weeks later they cut off AC the entire day during one of the worst heat waves in the area. Customer service completely unresponsive.
House temperature rose to the upper 90s on the lower level. I had it deactivated after that, and never reactivated it.
I'm curious who your power company is and how long ago that happened. If you're in the US do you happen to know if FERC got involved?
Utilities and grid operators that run retail-level demand-response programs typically cycle air conditioning units by turning them on and off throughout the day or by setting the thermostat a few degrees higher in more modern systems. I've never heard of a demand response program completely shutting off anyone's air conditioning for more than an hour, that sounds like either a technical failure and/or a wildly incompetent demand response program. Either way it's frustrating because it gives responsibly managed demand response programs a bad reputation.
Having said that, if the peaker plants are running full tilt and the demand response program isn't able to curtail enough usage then the next step is rolling blackouts. Is there a chance that's what happened, or did the rest of your power remain on?
Rest of power was fine, no rolling blackouts. Let me see if I can find any news articles from the time. I wasn't the only one it happened to, and apparently despite how it was sold, contract allowed for longer periods.
That's awful, if I had your experience I wouldn't use demand response either.
Now I'm also curious whether your contract was directly with your utility or through a 3rd party energy supplier. Where I live the non-utility energy suppliers can be a bit dodgy and push misleading contracts on retail users but they're still somewhat regulated so I am skeptical a contract that allows them to completely shut down everyone's AC for the entire duration of a demand response event would be approved here.
But I've heard horror stories about non-utility energy suppliers in other ISOs (like Texas' ERCOT) gouging customers, abruptly shutting down, or just generally being wildly incompetent.
AFAIK, there was no recourse either since it was sold as brief interruptions, but apparently it wasn't a screwup - they really had the option to just leave it off all day if the grid was really struggling.
And, while I appreciated the need, I wasn't going to be the sacrificial lamb next time that avoided the rolling blackouts. At least in a rolling blackout I'd get some AC.
basically the entire day. a little after sunrise as it warmed up, to after sunset. There was a couple of extremely brief intervals where it started back up, but basically an entire july day.
The UK smart charging regulations require all new domestic electric car chargers to be "smart." I.e. connect to a platform that tells them when they may or may not charge. They must have default schedules that avoid peak usage times if they are not connected. They must randomise start times somewhat so that there is no sudden surge of demand when the off-peak period starts, and so on. Many of the chargers on the market were doing these sorts of things already, anyway.
Nest does this in conjunction with local energy provider during "rush" hours. It will cool the house lower than normal, then raise the AC temperature limit, usually between the hours of 14-18. Actually get paid back for it.
No problem. I guess that would average out similarly, and be a lot more for some people. With solar, not so much, of course, but the load is also mostly absorbed. Interesting.
We have the same thing for shutting down our water heaters (geyser) - it is called a ripple control - sends a signal down the electrical circuit to houses from the local substation when there is power supply constraints.
Also works with electric boilers and ripple switches. They can hold temp for 24h+ so you don’t easily notice if the supplier kills it for a couple hours
Also excludes mention of solar installations and possibility of vehicles supporting V2L to support the grid in emergency.
Much of my take is, if you want an EV then you should be ready for solar as well. EVs and solar are a great combination that can support the grid in emergency.
That could be said about any opinion shared. Regardless of your opinion of my assertions, energy source and costs are a necessary factor in the economics of operating BEVs. If you can't source cost effective solar energy, it may not make economic sense (long term, as costs rise) to own a BEV for renters. Per mandates/subsidy, the subsidy already exists (may need adjustments), a mandate may be necessary.
You seemed to be making the argument that without solar owning an EV may not make economic sense for the EV owner.
I don't think that's related to the outcomes of the transition to an EV mandate for new sales, which is what the respondent was asking about. Sure, it's nice to have your own solar panels, but it's not a requirement for EV ownership, and I was pointing out that your assertion, whether true or false, was unnecessary for the EV transition to be a "good idea" in the parent poster's words.
That said, regardless of how you power your vehicle, even in some of the most expensive power markets, overnight charging is cheaper than gas, both economically and environmentally.
I would assume that the load through EV charging starts increasingly rapidly after work, which is precisely in that time period. But it's also not like they're singling out EV's. They mention a number of measures they'd like people to take to reduce electricity consumption.
But most EV's have settings to do delayed charging. In mine I can set it to either start charging after XX:XX or I can set it to be ready at a certain time, fx 7:00 in the morning.
In the deep past, given how many VCR clocks remained at 12:00 because their owners never set the clock, how many EV owners to you think are going to bother explicitly setting a "charge time" in their EV?
Unless it ships from the factory with "charge only during hours X to Y" preset and turned on, the vast majority are not going to get set for a delayed charge time, and will simply charge whenever plugged in. And their owners are likely to "plug them in" at the end of every trip so they are sure to be "topped up" for their next trip.
My utility gives me half-rate electricity if I charge after midnight ($0.11/kwh vs $0.23/kwh) - people will line up and wait for 20 minutes or drive across town to buy gas that's $0.03/gallon cheaper, I think they'll figure out how to set the 'delay charging' option on their car if it gives them the equivalent of half-off gas prices.
It's much cheaper for our town to charge in off peak hours. I'd be burning money if I charged my car after work, only for it to just be plugged in all night not charging when it's cheap.
For the US, no you are not "totally wrong". The majority of 11kW EV charge ports will have been installed by an electrician and also inspected by the local govt. electrical inspector because the vast majority of people simply do not try do to this work themselves.
However, in many locations in the US, homeowners are allowed to do their own electrical installs, provided they pull a permit and have the required inspection performed. Those should also meet code, as otherwise the inspector should have failed the install.
Which only leaves those who will do the install without pulling a permit and having an inspection. What percentage of the total those would be I do not know, but given that few do their own electrical work anyway, it is probably a very small percentage of the total. And a sub-set of those would do the install properly to code anyway, even without the permit and inspection.
Presumably if you install an 11kW (50A circuit) 240V EVSE, you're adding a new breaker to a service panel of at least 150A and going directly to the EVSE with a new cable. The risk of electrical fire would be minimal.
Math does not work here: 8h x 2kW = 16kWh. Tesla has 60 or 100 kWh batteries. It only works if you take only short trips (like commuting to work) and never go below 70% of charge.
It works perfectly fine if you plug in every night in your garage and don't drive more than 100km a day. If your commute is longer you might need 3 or 4kW, but probably not 11kW.
And if you take a longer weekend trip you'll need the whole next week to catch-up on charging. 11kW seems like necessity - it allows you to charge 0-100% overnight. No advance planning, no compromises required.
Also, I'm curious: in my country it is pretty common to have 11.5 kWh installation at home (it was even before advent of electric cars), is the US somehow limited in that regard?
American mains are single (split) phase 240v, your country's are likely 3 phase 240v. Your appliances are likely hooked to 3 phases simultaneously with a 20A breaker so they can get 12kW, American 20A hookup is only good for 4 kW (240x20x0.85 because you cannot draw more than 85% of max power continuously by code).
I lived for 7 years without a car in a big city. I finally moved to a place where cars were practical and will never go back.
No bus is point to point. Generally you need to walk, wait for the bus, take the bus (which is slower than driving because it makes multiple stops), get off the bus, wait for the next bus, and then repeat two or three times.
It can turn in 30 minute journey into a 90 minute one. Then you have to pay for the driver and the gas. If you live in a place where it is freezing cold or constantly raining that 15 minute walk to or from the bus could be a nightmare.
What about transporting things, like groceries? I couldn't carry both a gallon of milk and hardly anything else, let alone any small appliance. I relied heavily on Amazon and peapod, which is really wasteful and expensive.
We need to stop this obsession with public transportation.
That's the point, it's practical because it was designed that way. Intentionally. If you've lived in Europe, where mixed developments are the default, then cars are actually only necessary some of the times.
My cousins in France live literally 2 doors down from a boulangerie and get fresh out of the oven pastries in 5 min.
The ideal is that instead of using the car, you use your feet and it's even faster.
You can't beat physics. Sure, you can design things so that key facilities and services can be reached on foot, but you simply can't provide the same facilities that could be reached in a car radius vs walking radius.
Sure you can. I've seen it done numerous ways. France is a good example (above) - not only is the boulangerie 2 doors down, the others are literally within 10m away by walk. In Hong Kong, some of my friends lived in a tower where the grocery, post office, etc were all on the basement floor (and the elevators were unbelievably fast) - I swear it was the closest thing I'd ever seen in this world to Foundation/Trantor.
When thinking about a car, you also have to chalk-in parking and traffic. I bet you most people spend more than 10m door to door to their grocery store.
Assuming the Governor signs the bill they will be giving a $1000 tax credit for people who don't own a car. They put an income cap on it though, so I doubt it will have much impact.
It depends on individual circumstances. A thousand dollars plus no car payment, parking, insurance, maintenance, and fuel costs vs. public transit, occasional Uber and car rental might be attractive for some. It would've been much more effective though if they had gone with the original plan of $2,500 and no income limit.
The state is doing a lot on all three of these fronts.
Public transport is hard because construction costs are absurdly high in areas of high density, there aren’t enough people in areas with low density, and asinine restrictive zoning prevents increasing density over time. But it is happening.
In the meantime, people love their cars, and will continue to drive them. Banning cars entirely would disproportionately affect folks who have to commute long distances to afford housing, not great. So might as well mandate that the fleet turn over to something less harmful to the planet’s ability to support our way of life.
Can someone provide a reasonably unbiased take on the state of Californias electric grid? From the outside looking in, it seems their push towards renewables was perhaps too aggressive and now they are having issues meeting demand - but admittedly (living on the east coast) I am pretty ignorant on the intricacies.
As far as I know, the problem in the US in general isn't the amount of power they can produce. They have the prodcution and installation capacity to put up huge amounts of renewables (solar + wind) in a short time.
BUT the problem is that their electric grid is World War 1 era tech in many parts. The Camp Fire[0] fire was caused by close to 100 year old power lines mechanically failing.
This combined with the insane amount of permits and licenses needed to install new power lines makes this a tough nut to crack. (IIRC _anyone_ can complain about a transfer line as long as they can see it from their property.)
California’s electricity use varies a ton over the course of the year; in late summer the heat is most intense and peak demand is highest, roughly 50 GW.
The state is facing a historic heat wave this week, and the grid operator (California ISO) is asking people to voluntarily reduce demand. It’s not clear whether there is enough supply for peak demand without voluntary reduction, there probably is, but asking for voluntary reduction in the use of resource X (power, water, you name it) is par for the course in California these days. It costs almost nothing to do, and saves the utilities the high cost of marginal extra X.
It’s unlikely that the push for renewables has played the definitive role — peak load is after 4pm, when solar generation drops anyway, and baseline power like nuclear don’t help as much at peak because you can’t just spin them up for part of the day.
If anything the push to EVs has the potential to mitigate peak demand by tapping a fleet of grid-connected batteries at peak load, but that’ll require some coordination with manufacturers.
This is the point in the year that solar PV earns it's money back fastest, because peak yearly demand would otherwise use the absolute most expensive and dirtiest power.
You can also see their batteries providing slightly more than their nukes at these points too, again a very solid return on investment.
I’m in California, and it’s not bad really. I didn’t have a power cut of more than 15 mins in the last decade. It’s PGE which has been asking for lowering power usage a couple of weeks a year, in peak hours between 4-9 PM. Residential Solar usage is high compared to other states. It is hardly expensive for folks here to install a 10kW system, when housing costs are what they are. We charge our cars during the day, at work or home if wfh, between 10-4PM. Folks without solar charge them after midnight typically. If there are power cuts they are usually localized, and usually in areas with high fire risk(due to heat) so it kind of evens out in the end. Myself, I have solar and a EV and I keep my AC at 70 most of the day.
Yeah, it was a couple of years ago. I paid 30k for 12.8 KW system, including the electrical panel(which I had to upgrade for 2k). There was a federal rebate of 26% on top of that.
No. But I can tell you they mandated 'producing 50% of its electricity from qualified renewable energy sources by 2030' nd instead of building even more renewables asked PG&E to limit Diablo Canyon output to meet this internal goal.
>The main driver deterring PG&E from seeking a 20-year operating licence extension is the 2015 renewable portfolio standard (RPS) of producing 50% of its electricity from qualified renewable energy sources by 2030. PG&E’s model for the future cost of operating Diablo Canyon indicated that the cost per kilowatt hour was going to almost double, since the company would be forced to lower the amount of power it could produce from the plant in order to meet the state’s requirement. Dropping the capacity factor from the current 92% to say 50% would virtually double the price per kilowatt hour since costs are largely fixed.
>The state law which effectively dictates that by 2030 Diablo Canyon should operate at lower capacity each year and buy in power from intermittent renewables has apparently sealed the fate of the plant.
I'm also surprised to see this in context of the mandate that came this week from California to retire fossil fuel vehicles.
If current population and load is straining their power grid because it's hot they have some serious infrastructure to implement before 2035 rolls around. I'm sure it's not lost on anyone, just... the timing on the two articles is noteworthy.
A grid mostly powered by thermal electricity is going to struggle when it gets hot.
California does have serious infrastructure issues, mostly due to deliberate lack of maintenance on the part f the commercial operators trying to squeeze every dollar of profit out of their ageing infrastructure. There’s an entire distribution grid that needs to be replaced before it literally falls apart.
California has had problematic energy supply since the ‘80s. The problems have been getting steadily worse due to lack of maintenance, lack of upgrades, heat waves getting longer and more numerous, more frequent droughts, and poor water resource management.
There are a lot of people pushing this article on every social network. It’s a rude awakening to see how many people just take the headline and run with it before they spend any time considering the claims in the context of reality.
> A grid mostly powered by thermal electricity is going to struggle when it gets hot.
Maybe slightly. Britannica says (https://www.britannica.com/topic/coal-utilization-122944/Coa...) that most power plants limit steam temperature to 1000 F (540 C, 813 K). The efficiency difference when ambient goes from 300K to 310 K matters... a little.
I think it's more a case of "A grid that powers a lot of peoples' air conditioners is going to struggle when it gets hot". That is, the issue is demand, not supply.
Net metering is causing big problems for electric generators because tons of houses now use 0 net electricity, but still pull from the grid at night. The state is effectively turning the grid into a free unlimited battery for everyone and they haven't figured out the economics of that.
But they did. They pay 2-3c/kW for excess electricity generated during the day. Their own generation costs are 6x that. PGE so far hasn’t been losing money on residential solar installations. And rise of EVs augurs well for their future demand. So far renewable energy generation during the day rarely touched 100% of consumption. It has to go beyond that couple of times over, before it makes a dent in PGE revenue
People not understanding the duck curve is a pet peeve of mine and I thought it had died out over time but that article is only months old and full of misinformation.
The duck curve "problem" is that the gas plants need to ramp up fast. If they can't ramp fast enough, you need to start them slightly early and turn some other more easily adjustable source down, usually wasting solar.
The fix, apart from just asking gas plants to ramp faster, is battery storage. When the duck curve was first discussed you couldn't even get cheap solar, never mind cheap battery storage and they thought that this small waste of solar might prevent it being cost competitive. This did not turn out to be a problem anyway, but batteries also fixed it.
You can see the batteries charging and discharging on the CAISO live graphs.
But, it is not about the height of the peak. We have more than enough capacity to meet the peak because we build enough for the yearly peak which is higher than the other peaks. We just didn't have stuff that could ramp fast enough. Now we do. Batteries.
Building coal or nuclear as that proposes does nothing to solve this problem.
EV are helpful, because we can charge them when we consume little energy (at night) or when we generated to much renewable energy (solar). We just have to incentivize charging at the right time and to pay EV owner to make their battery available for the grid as a virtual power plant (see https://www.tesla.com/support/energy/powerwall/own/californi... currently set up for powerwalls but could support EV once most of their battery are LFP)
I am not from the US but I have a somewhat intelligent charger. It can communicate with the power company and be set to only charge my EV when the load is not high (it still guarantee the amount I want charged, so I wont risk not having my car charged).
If thats turned on they give me an approx 12% rebate.
I am in Southern California and have special EV electric rate that offers much lower rate between 9PM and 1PM. However, between 1PM and 9PM, the rate is a bit higher overall. The charger has this info and won’t generally start charging the car until that time unless overridden.
I’ve done the math multiple times. It makes no sense in my area. I would pay more for panels then I would save in electricity. Once the panels are paid off they need to be replaced. If you don’t buy a battery you have to rely on the good will of the power company to pay fair rates for 30 years. Those rates were cut in half last year. The battery only has a 10-year life expectancy so needs to be financed over that time period or less. You’ll have to pay for removal and re-installation when your 15-year roof needs replacing.
It also depends where you got your quotes and estimates. Retail sales reps are a complete disservice to the industry, often quoting double what an installation _should_ cost.
I highly recommend EnergySage for quotes. It's free and unbiased for sourcing local installers while skipping the sales reps.
And do keep in mind warranties cover 90% efficiency on panels and they'll continue working beyond warranty at reduced capacity.
Some don't have an ideal roof layout (which can easily double costs). Even more so, trees can sometimes be in the way, which can be even more inhibiting. 2-3x cost can still see an ROI, but when you get into 5-10x cost things tend to break down.
Panels are great for VERY SPECIFIC USE CASES. They do not fill the role of energy security.
You need reliable , clean nuclear plants. The ones from fifty years ago are great, imagine what we could do if the fucking NRC stopped adding such incredibly dumb and onerous requirements on any new permits for new tech.
I too am in favor of nuclear energy to supplement solar and other renewables because we can't afford to pick and choose favorites for net zero at this point, and indeed it will help to bridge windless cloudy days, but this is just off the mark. Solar panels are not so specific, especially not when it's the sun's heat that causes people to use more energy on cooling.
>The ones from fifty years ago are great, imagine what we could do if the fucking NRC stopped adding such incredibly dumb and onerous requirements on any new permits for new tech.
I'm in France, where we should get ~78% of our electricity from nuclear. But half the reactors are down partly due to issues with the old reactors and maintenance problem (planned or not). https://nuclear-monitor.fr/#/mix
So electricity is crazy expensive and the government just hold an emergency meetings (minutes ago) to try to find a solution before the winter. Some manufacturers (esp in the glass business) might go bankrupt as they cannot turn of their plants…
I wish I could install solar panel on my roof (but I'm in Paris and the building is shared among by many owners so it isn't easy to get them on board).
No plan for a backup, those aged reactors more than served their time.
The word you're looking for is "Incompetence". It is also poetic that the present fleet of French Nuclear plants was built to wean France off another energy crisis in the aftermath of the oil cartels moves. It seems history repeats itself for those who dont learn from it.
No. Only Fessenheim has been closed and it accounts for a very small % of the power that currently lacking (1.8 GW at best vs 37.8 GW of the whole fleet).
34 reactors are off now + 4 partially down. You can't blame this on a single plant and politicians, especially when we can't build a working EPR [0], and when the old ones have defects (corrosion) that require them to be turned off in the middle of an energy crisis [1]
1. Phase out all active reactors without a plan for extending their life
2. Reactors reach end of life gracefully. France decides to extend their life since they don’t have any backup energy sources.
3. Cry that 34 reactors with the same rough age and same design are down for preventive maintenance since they start showing signs of aging.
Are you insane, stupid, malicious or just ignorant?
The grid is failing on hot days because of the amount of thermal generation they still use. When it gets hot, thermal plants produce less power because their production capacity is related to the difference in temperature between their steam and the ambient air.
Nuclear plants are thermal plants. They are not magic. They have to abide by the laws of physics.
The VERY SPECIFIC case is adding power to the grid? How many other situations besides continuous power and intermittent power exist that makes it a "very specific" case?
I can add as much power to the grid as i want to, if there's no storage and demand is low, that makes zero difference to the grid.
Storage being what it is, we either accept the costs of routine (10 year cycle) swap outs or we dont. Simple. Oh, and please remember that present demand will be a fraction of future demand and hence any storage you build must grow in capacity over time.
Photovoltaics serve a very specific use case of aiding domestic energy production at times when conditions are right. They are great for a lot of reasons, but for cases where there is a high demand for reliable supply such as industries producing things, they are . . not the first choice.
Given the equivalent amount of dollars spent by an entity as large as the state of California, with the laws of physics as we know them today, there is only one logical solution in Nuclear energy. The energy density and scale just can not be beaten.
Build a FUCKTON of nuclear plants and never worry about a fucking electricity bill ever again.
Want to keep the Air conditioning on while you're not even home? Yup, No one cares.
Want to run an audacious amount of carbon capture devices near dense population centers? Yep, absolutely.
Want to desalinate the waters of the pacific and have it ready to pump inland during large scale drought? OF COURSE!!!
The trouble with Nuclear is that it invalidates all the reasons for "Green" politicians to impose excessively wasteful and stupid ideas that dont work, but serve as a slush fund. If we wanted to solve this great pressing carbon emissions problem, we would be building a large nuclear base.
For anyone who's reading this comment and thinking "Wow, AC all day?? What a wasteful way to live!" Congratulations. You are immune to the audacity of using science to solve problems that previous generations considered impossible.
An infinite amount of energy represents the greatest opportunity for humanity for a thousand years. We should have invested and take a giant leap in our quality of life half a century ago.
We're building one nuclear reactor in the UK and it's so expensive it has been dubbed "the most expensive electricity on the planet" and has almost bankrupted the French energy company which is constructing it. It's also taking many years longer than planned to finish it. If your plan happened, "cheap energy from an expensive source" means low profit and low return for the investors of the power plant. USA is not faring much better in the 'showing it can still build public nuclear power plants' stakes, or in the building large public construction projects quickly and cheaply stakes.
See my previous large comments with details on pricing, build times, cost increases in nuclear power, before dismissing this as a throwaway comment:
One-off projects are usually incredibly expensive because you have to make everything custom. I don't think this argument "scaling up must be expensive because our one-off project is expensive" goes. Doesn't one usually expect to pay 5-10× as much to have something made custom as opposed to a common product?
There's on the order of 500 of them in the world if I remember wikipedia correctly. I wonder if any country built enough shortly after reach other / in parallel / same company building in multiple countries at the same time to see an effect of scaling (materials, knowledge, experience, navigating the legislation, ...).
Furthermore, energy being X% more expensive for the next hundred years might just be the reality we have to live with in order to reach net zero realistically. (Looks like this is happening due to gas prices right now anyway, so we might as well have gone nuclear... ten years ago it was obvious that we would want to stop burning gas some time soon, but not that solar panels would become so cheap so fast, so it would have made sense, and yet...) The alternative to spending a bit extra on your energy bill is spending way more on climate adaptation, from growing food to relocating people to building sea walls in many if not most countries.
South korea is by far the biggest producer of nuclear plants. Their prices have gone down slightly after building dozens of plants, but nuclear is still more expensive than solar for them. Until we get a legitimate fission innovation plus the political will for deregulation nuclear prices will remain sky high.
Also more expensive than climate change adaptation?
I know it's a big and, truth be told, unanswerable question I'm asking. I just mean to say: can we really afford to pinch pennies here, comparing the cheapest forms of energy we have today (like solar) as a benchmark which it must beat before we consider a low-carbon low-landuse low-risk* base load to be a good addition to the grid?
So long as it's not prohibitively expensive, at least.
* near-negligible chance but a fairly large impact (not in death/cancer toll, at least not compared to gas/coal even if you scale it per kWh, but in evacuation and cleanup costs), at least when not considering that we might build better reactors than we did in the 60s (even if we probably would) (Fukushima and Chernobyl were designed before my parents were born and I'm not a teenager anymore). I can see how people find this not danger-free, even if most of it is misguided, especially when you're not near the biggest fault line of this planet
Uncouth way of putting it, but I think you hit the nail on the head. A massive increase in the available energy supply would allow us to do things we can barely dream of these days. To me, it almost feels like energy availability corresponds to how advanced the society is, and from that perspective it's weird to me that there's such a push for actually reducing our energy usage and output.
Nuclear power is among the most expensive forms of energy available to us. "Too cheap to meter" never materialized. A "FUCKTON" of nuclear plants will also take decades to build and produce zero power while under construction.
That might or might not be the true cause for the high price of nuclear. But in any case the chances of us getting rid of the regulations in the next five years are essentially zero. So any hopes to have abundant, cheap nuclear power this decade, or even the next, are pipedreams.
> Want to keep the Air conditioning on while you're not even home? Yup, No one cares.
Switching off AC for 8 hours (1/3 of day) when you are not at home doesn't save even 10% of energy, you will just burn the "saved" energy trying to cool down the house when you will switch it on again. There was study published just last week about it.
> you will just burn the "saved" energy trying to cool down the house
Did you read the article you linked? It says:
> What we found was that even when the A/C temporarily spikes to recover from the higher indoor temperatures, the overall energy consumption in the setback cases is still less than when maintaining a constant temperature throughout the day.
Even if you ignore the whole thing (as I should have, I was validating their method because the conclusion you cited sounded wrong... but then it turns out the conclusion isn't what you claim) and just read the concluding two sentences of the post, you'd have read: "An eight-hour setback on weekdays provides savings regardless of the system type"
It's a convenient myth that not turning off the heating when you're not home saves energy because the heater would otherwise have to work extra hard when you come home / wake up and consume more energy. I've heard it told by people that usually have sensible opinions. I guess it's the inverse myth in the hot places of this world. It is indeed very nice to walk into a climate-controlled place, so I can see why people love to believe it.
It makes no sense. Think about it: in the scenario where you let the AC run all day long (or leave the heater on overnight), the temperature differential between inside and outside is larger. More heat enters/leaves the house when the differential is greater, so it makes sense to let this grow smaller when you're not there anyway and only increase the differential when you're (almost) coming home or coming out from under the blankets.
Why would a heat pump run more efficiently when maintaining a temperature differential? From my rudimentary physics knowledge, a heat pump works best when the temperature difference between hot and cool side is lowest. So the first Joule pumped out of a warm house is the cheapest.
I'm having a hard time finding good information on this, or at least I was a few months ago when I was looking into whether I'm being stupid for thinking essentially what I said in the last paragraph. Do you have a link where I could read more about why it makes sense for heat pumps? I don't understand why the same logic shouldn't apply there.
> That is to say, if a property lost 40kW/h of heat through its walls throughout a 24 hour period, that typically doesn't mean you have used 40kW/h of gas from your boiler or 40kW/h of electricity from your heat pump.
> If the boiler has consistently run at 85% efficiency you will use 47kW/h of gas. If you can get 93% efficiency from that same appliance you will only use 43kWh gas.
> And therein lies the problem. Many arguments for turning the heating off are talking about saving heat loss, not saving primary fuel usage. The difference between the two relies heavily on the first variable we need to ask ourselves, what is our heat source?
(That "kW/h" is a red flag for me. I'm not super knowledgeable about electricity myself, so if a blog can't even tell kWh from kWh/h from kW/h, I usually try to avoid it. Anyway, this is not a random source that I found but something being vouched for, so I'll trust it.)
This seems to be the core argument:
> most people have condensing boilers. These can run at lower temperatures which cause some of the fumes to condense into liquid water (hence the name). And this action extracts extra efficiency from the appliance.
> If you have a heat pump, the gains from running at lower temperatures are even higher here. Running at high temperatures of 50 to 55°C all the time year-round to maximise the responsiveness of the unit, and switching the heat pump on and off regularly will result in [~half the] efficiency.
I like this comparison:
> It's a bit like saying, I'm going to drive 100mph to the shops as I'll only be driving for 30 seconds. Actually, if you drive at 5 mph you will take 3 mins, it may ‘take longer’ but it will be much more efficient with fuel.
Because it also highlights the fallacy: this is wrong. At 5 mi/h, my car uses something like 30l/100km (rough estimate, maybe +/-10). At 40mi/h, it's around 3.3l/100km if I remember correctly (+/-0.3). But, yeah, at 100 mi/h you're obviously battling a lot of air resistance and slower would be more efficient... just not excessively slow.
The article would benefit from some actual numbers. It explains the general concept, but how many hours would you have to leave it off for, for it to be more efficient again? Is there a formula or curve to use with time on the X axis and... house volume or outside temperature on the Y or something, or are there too many variables to dumb it down to a line that works as general advice per heater type in typical climates? Surely for those that don't work from home, using reverse AC to blow some hot air, for 15 minutes in the bathroom and 30 minutes in the kitchen while you get ready in the morning, is more efficient than having base heating turned on during the 8 hours that you sleep + 2×45 minutes that you commute + 8 hours that you work?
But I understand the concept at least, thanks for the link!
The link at the bottom about why zonal heating doesn't make sense gets deep into the numbers and calculations.
I hadnt read the Ars Technica link before, but it makes the same argument, with graphs, a low efficiency device in a poorly insulated home left off for a 4 hour period makes sense, but in that situation you probably want to insulate and/or use a more efficient heat pump rather than do that.
Did you read the sentence after the one you quoted? It then says
>On an annual scale with a conventional central A/C, this could result in energy savings of up to 11 percent.
That's basically what the poster above was claiming (though they seemed to be under-estimating the effect a little). Obviously turning the AC off will reduce the amount of heat leaving the house, but the point is the gains are not super large, even with an inefficient AC and a poorly insulated house. If you have an efficient AC and a well insulated house then the difference could be even smaller (it's even possible that the trend could reverse at some point, if the efficiency of the AC goes down when it is pumping more heat to cool down faster as opposed to consistent low-power heating: you can actually see this in the charts if you look at the mini-split system: it actually uses less energy to turn run the system all the time than to have it off for 4 hours a day, though 8 hours off time is still more efficient). Add in the effects discussed elsewhere in this thread where not all energy consumption is equal from the point of view of the grid and it may even make sense to do the opposite: run the A/C hard during the day while you're not home but green electricity is cheap so you can have it off when you get home and elecriticy demand spikes and solar power is falling off, flattening out the dreaded 'duck curve'.
Yes I read and you can see clearly on charts switching of AC for 1/3 of time (8 hours) saves only ~10% energy. So yes, you will save negligible amount of energy by having switched off AC for non-negligible amount of time.
> It's a convenient myth that not turning off the heating when you're not home saves energy
Stop twisting my words, I didn't say anything like that, I just said thosae savings are negligible and irelevant.
Not just you who's saying that, but it's a thing that keeps being repeated. You didn't say it helped at all, while in reality it does. That's the thing people are going to remember.
Ask anyone if they want a 10% discount on their energy bill (while helping the environment / energy transition to boot) and see what they say. I don't think it's going to be "nah, not worth it".
I said "it doesn't save even 10% of energy", maybe work on your reading skills if that means for your it doesn't help at all.
Yeah and ask those people if they wanna come for this saving to hot home. This negligible at best 10% discount ain't for free, it cost you convenience which I value at more than some negligible saving.
Nuclear is a political loser. Making it affordable requires massive deregulation which will absolutely end up costing votes, and it'll only show benefits after a decade, so no politician will support it.
Yup, because nuclear power requires humongous government investment, so the party of small government is never going to go for it, while nuclear has a bad reputation both from a cost efficiency, lead time, and a safety point of view, so a progressive party is not likely to go for it when renewables are a much more attractive looking solution.
I thought you have a "fossil fuels are cool and manly" party and a "fossil fuels are important for corporate interests" party. But that's just my impression as an outsider.
I would have said "Renewables (but really mostly just fossil fuels) Party" but recent legislation makes it seem like the Democrats may be getting more serious on renewables.
If you read, it’s promising that EVs can actuallly be upgraded with tech that will have EVs plugged in will be a great help. And banning them now isn’t going to have a meaningful impact on the number of EVs this summer.
The thing that’s despicable is the lack of nuclear power. A few more plants would completely stabilize the grid.
Nuclear power is good for providing base power not for reacting to spikes in demand. You cannot just spin up production of a nuclear power plant when you need it and shut it down when you don’t. They’re always producing so when demand is low, they’re producing too much and wasting it. If the California grid cannot meet its demand at its lowest, then yes, base power like nuclear would be a good solution. Heatwaves generally pass though.
That's pretty much the same issue you have with renewables, especially wind. Sometimes it will just produce more than you need. The solution is the same: use overproduction to produce hydrogen or for desalination plants. It's actually easier in the case of nuclear, because demand is more predictable than weather, and you have excess energy day, not only on a few days per week or month.
> The solution is the same: use overproduction to produce hydrogen or for desalination plants.
Does anywhere actually do this? Storing hydrogen at scale seems insanely difficult and desalinating water wouldn't let you use the energy later. AFAIK, most places deal with surplus energy by putting it into a big battery, usually the physical kind of battery like pumping water up hill and holding it behind a hydroelectric dam.
Many pumped hydro station were originally built to use cheap overnight electricity from nuclear plants when demand was low, and timeshift it to spikes of demand later.
Ok, so industrial users buy hydrogen. And then how do you convert the currency they give you into energy when you need it later? If you're just trying to find an economic use for excess power, you might as well mine Bitcoin.
> You cannot just spin up production of a nuclear power plant when you need it and shut it down when you don’t. They’re always producing so when demand is low, they’re producing too much and wasting it.
Yes you can, pretty much any plant built in the past 20 years does that and in France/Germany even older plants have been designed to do it.
(Economically it's undesirable of course, because the marginal operating cost of a nuclear plant is very low.)
I think the financial markets can solve this. People like me who like the luxury of having reliable electricity every day of the year can buy futures from a nuclear operator. And people who don't mind cooking in the middle of the night or having a week-long power outage now and then can buy solar or something on the spot market.
A surplus of energy is always better than a deficit.
You could have scheduled applications to divert the energy to if storage is not built out. Desalinate the pacific, for example, pump the water inland for drought time when supply exceeds demand.
1. Nuclear can be built safely to handle emergency scenarios. It's not the catastrophe you see in movies. Fukushima which used a very primitive design, suffered from bad maintenance, and suffered a historic tsunami, still was kept fairly safe.
2. You don't built right ON the fault line. Electricity delivery over long distances is a thing even without HVDC. The fault lines for Diablo Canyon were discovered after the fact but the design was adjusted to handle that information.
3. New reactor designs are waaay better. And guess what. The more reactors we build, the more nuclear scientists there are, the better we get at building them. Why do you think America, the country that invented nuclear power, has 55 plants while China ALREADY has 47 with another 11 along the way while most construction started ~7 years ago. China is going to absolutely OWN the US on energy policy unless we get our head in the game.
I guess a nuclear reactor is only 2 typical coal plants so they'll need to 10x their current nuclear capacity to get rid of coal.
The only annoying thing is they're still building coal plants. I don't understand what I'm missing since nuclear is supposed to be cheaper. Maybe SNF still poses a logistical challenge they can't handle vs venting CO2 into the atmosphere.
Between 2pm and 7pm (I think those are the hours) the company can shut down your AC for 20 minutes at a time.
I can think of twice in 15 years that I noticed it. For that you get a small discount on power June through September.
Good deal.
I like that this allows for more immediate / targeted impact for folks managing the grid.
Something like this for car charging (or even just slower charging?) might be useful?
https://mn.my.xcelenergy.com/s/residential/heating-cooling/s...