
How Cheap Can Solar Get? - prostoalex
http://rameznaam.com/2015/08/10/how-cheap-can-solar-get-very-cheap-indeed/
======
RamezNaam
Hi. I'm the author of this blog post. Happy to answer questions people have,
as time allows, on Wednesday.

Upcoming posts will look at the future of wind power, the future of energy
storage, and what the missing pieces are.

If you don't want to wait, you can read my thoughts on energy storage here:
[http://rameznaam.com/2015/04/14/energy-storage-about-to-
get-...](http://rameznaam.com/2015/04/14/energy-storage-about-to-get-big-and-
cheap/)

~~~
nroets
IIRC all the efficient solar cells we currently have contains some rare
materials. Once a particular solar technology reaches grid parity, the demand
for the relevant rare material will increase, placing a floor under the price
of that solar cell.

In the case of Moore's Law, a transistor can be any size. By contrast, solar
cells absorbs too little energy if they are too thin.

TL;DR: There are real physical limitations to solar cells.

~~~
RamezNaam
Two things have happened in this area recently.

1\. The grams of rare earths required per watt of solar have been dropping
steadily. And Solar PV panels with no rare earths at all have been developed,
though they are not yet common.

2\. "Rare earths" are not so rare. Their prices have tumbled substantially as
new mines have opened up and substitutes have been found.

~~~
joshuapants
> 2\. "Rare earths" are not so rare. Their prices have tumbled substantially
> as new mines have opened up and substitutes have been found.

Yes, but mining them is an environmental disaster.

~~~
mikeash
Can you quantify that? I'm seeing comments in this thread saying, over and
over again, that manufacturing these things is an environmental disaster. But
without numbers, the statement is meaningless. We are _currently_ poisoning
pretty much the entire planet for our energy needs. If we cut that down to,
say, poisoning an area the size of Texas for our energy needs, that would be a
_massive_ win.

~~~
DennisP
Solar is definitely far better than fossil. It's just not entirely clear that
it's better than nuclear, especially with the advanced reactors that get a
hundred times as much energy from the same fuel, and produce only a small
amount of short-lived waste.

------
fpgaminer
If I could install solar today I would, regardless of cost (apartment living
prevents it). That may sound crazy, but I theorize that when you consider
externalities the cost of grid electricity already far exceeds the cost of
solar. It's going to cost humanity a whole lot of money to both survive and
fix the damage we're dealing to the environment today. I'd rather pay more now
for solar, than pay through the nose later for the environmental equivalent of
a triple bypass surgery.

I doubt others see it that way, so I guess I'll pay the cleanup cost later
like everyone else regardless. Such is the human condition.

~~~
rm_-rf_slash
I used to think this way until I started dating a geologist. She brought down
my optimism when she detailed the ways that the environment is ravaged to
extract the materials necessary to create solar panels, wind turbines, and so
on. Rare earths are great for handling high heat, but their resistance to
reaction also means it takes a LOT of nasty chemicals to purify the ore. Not
that we should keep on burning fossil fuels, but we shouldn't kid ourselves
into thinking that renewables are a one-way street to environmental
prosperity.

~~~
ZeroGravitas
Not all PV panels, wind turbines or EV car designs use rare earths e.g. Tesla
doesn't use any in their motors.

Also, lots of other things that aren't good for the environment use rare
earths. Kind of weird and illogical that people only care about it when you're
trying to do good.

~~~
castratikron
Are you sure about Tesla? What material do they use for the permanent magnets
in their motors? I know the motor has to contain permanent magnets since Tesla
cards have regenerative braking.

~~~
pjc50
[http://my.teslamotors.com/roadster/technology/motor](http://my.teslamotors.com/roadster/technology/motor)

No magnets, induction motors.

------
justaaron
i live off grid inside of a 500w/h peak footprint. i paid around $1000 for
proper German (Schutten) panels, a charge controller suitable for them, 2
110ah "solar batteries" (lead acid usual cheapo old school stuff), and a
Xantrex inverter. After nearly 1 year running a fridge, lights, computer,
router, & studio monitors, I'm ready to add more battery capacity before the
winter (cloudy days) and a small wind turbine.

grid-tie systems are another story and a bigger investment. (need a proper
electrician to wire it etc...)

feeding ignorant "city ways" in terms of people's silly habits fed by years of
cluelessness (no a hairdryer will never ever be possible, as that's 2kw right
there...) that's where the biggest expenses come in... if you don't try to
keep up with the usual clueless electrical consumption, a well organized
person can begin cutting their footprint down...

for example my alleged 85w macbook pro power supply consumes less than 20w
typically... my inverter says so...

~~~
watchdogtimer
Do you always use your MBP connected to a power outlet? If so, try running it
until its battery is drained about 50%, then plug it into your inverter and
see how much power it draws. My guess is it will draw about 50-60 W.

I've been using a pedal-powered generator to power my computer, phone, tablet,
and LED lights for the last 5 years and have tested several laptops and other
devices using it. I've found that most laptops draw from 12 W (11" Chromebook)
to 25 W (older 15" Dell) when their battery is charged, but 40-60 W when
charging. The power supplies of most devices seem to have about a 50% safety
factor, so a device that has a normal max power consumption of 50 W will use a
75 W power supply.

~~~
mikekchar
How much electricity can you generate? Just thinking off the top of my head,
I'm a sucky cyclist so can only manage about 150W power output sustained,
probably. I'm not sure I could handle more than an hour of stationary biking
before I collapse in a puddle of sweat ;-) So that's about 150 WH...

Is that about right (ballpark), or have I missed something? It would probably
power my laptop for the day, anyway... It's something to think about (since I
love cycling, even stationary ;-) )

~~~
watchdogtimer
Most people seem to be able to comfortably produce 30 W over a sustained
period of time.

If you're used to bicycling, dress appropriately, and work in a cool
environment with a fan, you can produce 50-60 W.

Above that, it becomes difficult to maintain your concentration on your work
while trying to pedal hard at the same time.

On most days, I maintain about 35-50 W, depending on the load.

So far this morning, I've ridden for 2 hrs, 5 minutes and produced 74 W-hr.
The computer I'm using this morning is a Raspberry Pi2 with a 19" monitor. I'm
also powering our DSL modem/router and a 12 V fan while recharging two
tablets, four AA batteries, and my phone at the same time.

------
1971genocide
Does anyone know methods for hackers to help and learn more about solar ?

It it possible for the mathematically trained to easily immerse and innovate
in the industry ?

It it possible to manufacture solar cells "in your garage" so to speak ?

~~~
chm
My MSc is concerned with a model for simulating molecular photovoltaics. The
work I do is a blend of physics, chemistry, maths and programming, in
different proportions. I wouldn't say it was "easy to immerse", but complement
your skills with physics/chemistry and you could be useful, yes.

A Grätzel or dye sensitized solar cell can be easily created in your garage.
Look them up on Youtube.

~~~
selimthegrim
Better models for molecular photovoltaics are sorely needed. Math skills are
not unwanted.

Source: I work in the field.

------
jl6
Does this make solar a great industry to invest in because of the growth
potential, or a terrible industry to invest in because the prices are racing
to the bottom?

~~~
RamezNaam
Hi. I'm the author of the original post. The amount of solar installed in the
world is going to scale by more than 10x in the coming decades. There will be
more than a trillion spent.

If you pick the winners, investment will have huge return.

Most solar companies, however, will be casualties in the fierce competition to
come.

The other area to look at is energy storage. More renewables will increase the
demand for energy storage. And it's early days in that field. Again: Huge
returns for the winners. But most companies will be shaken out of the field.

~~~
draugadrotten
Do you have any suggestions about good solar startups with good
patents/tech/people?

~~~
eigenvalue
The race to the bottom is more applicable to the panel manufacturers. The
lowest cost producers are mostly Chinese companies, and the financial
performance for these companies (ReneSola, Yingli Green Energy, Trina Solar,
etc.) has been pretty terrible so far. Probably the best way to invest in
solar through the stock market is to invest in a developer of solar projects.
The best of these in my opinion in terms of scale and expertise is SunEdison
(ticker: SUNE), and incidentally, the stock has been in free fall for various
reasons over the past couple weeks, so this is probably a reasonable entry
point.

------
hwstar
I have a 1kW solar panel battery storage system which I use to power my
computers and servers. I installed it a couple of years ago to help mitigate
the $0.37 kWh top tier rate that SDG&E charges.

In California, a minimum charge was introduced and will be $10.00 starting in
2016. I suspect that this charge will be jacked up in increments till it is a
significant fraction of the monthly bill.

If this does indeed play out, then the only option will be solar with
localized energy storage, and disconnect completely from the grid.

California also will be flattening the rate curve at the Utility companies
request to combat solar installations in the next 1-2 years. Users in the
first tier will be paying more, the other tiers will be combined into one and
be at a lower rate than the current top tier. In 2019 there is a plan to move
everyone to time of use pricing. Once time of use is mandated, it may be too
expensive to remain connected to the grid.

~~~
RealityVoid
What you're saying does not make sense from the utilities point of view. Why,
if they have superior competition, would they make themselves more
uncompetitive?

Besides, centralized energy systems have certain advantages that household
operations do not have. Maybe even better ones will arrive once solar becomes
more accessible. SO it makes sense that they will stay at least as competitive
as off-grid systems.

~~~
tired_man
Can't keep customers? Then charge the ones you do have even more to make up
for that shortfall.

Businesses trying to keep their outdated business models alive do that sort of
thing all the time. Just look at the music and movie industry's continued
flailing as they try to keep CDs/DVDs profitable while their customer base
wants files that they can play on _any_ device they own, not a physical copy
or some DRM-laden crap that forces them to use it on one system.

------
erikb
I'm not happy with the diagrams. Example: the first one compares time to
costs. That's really what we want. But why not add some lines for traditional
ways to make electricity? That's what we want to compare to, or don't we?

------
leni536
What is the environmental impact of making solar cells?

~~~
chm
Sorry for the non-answer:

The term "solar cell" refers to a wide variety of technologies[1]. Anything
from common semiconductors, rare-earths or even fruit juice can be used to
make solar cells. The impact will be highly dependent on the type of cell in
question.

[1]:[http://www.nrel.gov/ncpv/images/efficiency_chart.jpg](http://www.nrel.gov/ncpv/images/efficiency_chart.jpg)

The above graph isn't all-encompassing.

~~~
leni536
Fair enough. I think the most satisfying answer would be the released
chemicals and other environmental effects normalized to kWh for various cell
types, taking the designed lifetime and recycling into account maybe with some
emphasis on cell types that are currently sold for households, or planned to
be sold in the not too far future.

I'm interested in these questions:

\- What cell types are currently bought, will be bought in large quantities?

\- How it affects / will affect the environment?

~~~
pjc50
The first of these links gives an overview of the risks, pointing out that it
depends very much on the particular factory's safety record. I don't think
normalising is even possible across so many different possibilities. All the
risky chemicals _can_ be recycled and non-CO2 emissions neutralised, but this
is not always done. It also says the majority type sold is polycrystalline, so
CdTe are rare. (Both cadmium and tellurium are quite nasty, but also bound in
by the manufacturing process and not prone to leaking)

[http://spectrum.ieee.org/green-tech/solar/solar-energy-
isnt-...](http://spectrum.ieee.org/green-tech/solar/solar-energy-isnt-always-
as-green-as-you-think)

The second addresses the carbon cost specifically.

[http://info.cat.org.uk/questions/pv/what-energy-and-
carbon-p...](http://info.cat.org.uk/questions/pv/what-energy-and-carbon-
payback-time-pv-panels-uk)

------
nell
If solar is really that viable of an option, India should be investing a lot
in this research. Power is a huge problem there. 24 hours of power supply is a
luxury even in top cities. Small industries in rural parts operate around
availability of power. There are a lot of wins here. And guess what, there is
a lot of sunlight in major parts of the country throughout the year.

~~~
ZeroGravitas
There's a lot going on (note that wind is currently cheaper)

[http://cleantechnica.com/tag/india/](http://cleantechnica.com/tag/india/)

------
mark_l_watson
I installed solar a few years ago. I didn't do it for economic reasons, rather
because I wanted to.

There is now push back by the dominant power company in my area against solar.
When I got solar they gave me a small grant.

Solar is the future I think. Too much potential danger from nuclear and coal
polutes too much.

------
europestup
We all know that PV panels have a limited lifetime, and that building them has
environmental cost. But I was wondering about recycling: does anybody know how
much energy can be saved by creating new panels using materials from old ones?

~~~
andyjohnson0
Not really answering your question, but as far as I know panel lifetime is
largely determined by cumulative damage from the environment. Scratches from
trees, etc. reduce effectiveness, as does rain leaking into the panel through
gaps created by the daily thermal cycle. There may be a lot of scope for
extending their lifetime by improving packing, which would defer the
environmental impact of recycling. There is some info on these factors in [1].

Also, panels may be declared end-of-life because they are not as effective as
newer ones, even though they are still generating to original specification.

[1] [http://energyinformative.org/lifespan-solar-
panels/](http://energyinformative.org/lifespan-solar-panels/)

------
JoeAltmaier
Power-company solar may matter more than rooftops, in the end. They have the
economies of scale, choice of location and orientation, grid connection
expertise.

------
arkem
Off topic but Ramez's novels are excellent, have a look at Nexus!

