
Cost goals met, the DoE is moving on to address grid reliability in solar - vasili111
https://arstechnica.com/science/2017/09/solar-now-costs-6-per-kilowatt-hour-beating-government-goal-by-3-years/
======
tryingagainbro
This might actually work. A lot of of the dirty work can be done in places
with solar /wind power and during the peak energy producing times.

Like for aluminum smelting which apparently needs ~10x the energy that steel
needs [https://theconversation.com/the-trouble-with-
aluminium-7245](https://theconversation.com/the-trouble-with-aluminium-7245)

~~~
sremani
But they can do that right next to hydro-electric plants with much more
reliability.. If I am not wrong, Alcoa did shutdown their plant in central
Washington (crypto-valley), so aluminum smelting is probably not that rage
anyway.

edit: Crypto-mining may be one alternative, you are converting energy into
currency is the most straight forward fashion. Could be the way, who knows.

~~~
adrianN
It's hard to build airplanes out of Bitcoin. That aluminium must be produced
somewhere.

~~~
sremani
The point, If they are closing Aluminium smelting plants when they are being
sold 2cents/kwh from a reliable hydro-electric plant. Wind and Solar's chances
are slim to none.

I am not questioning the utility of Aluminium here.

------
peeters
So are batteries the only viable storage solution? Does any other storage
compare in terms of price and scale? (allowing a dollar value to be put on
efficiency)

If not I'd assume Tesla would be well positioned there, but I wonder if even
it could scale that far.

~~~
Robotbeat
Don't underestimate pumped hydro. It's already at about $125/kWh.

The Bath County Pumped hydro station stores about 35-40 GWh of power (35,000
MWh), cost $1.6 billion in 1977-1985 or so (so inflation-adjusted about
$100-150/kWh).

Compare to the largest ever battery storage project, the Tesla 129MWh
installation in Australia is "guaranteed" for $250/kWh, but that doesn't
include a lot of extras (the storage facility has a pretty high discharge
rate, able to dump its storage in roughly 1.3 hours vs like 4-8 hours for
better battery life and lower secondary costs).

So in terms of cost and scale, pumped storage steal beats the best battery
installation by a factor of 2 (not counting likely longer service life before
replacement, although that depends strongly on how hard you cycle the lithium
batteries), and scale-wise beats it by a crazy factor of 300.

Pumped hydro does have some geographical constraints, but there's a lot more
opportunity to build them than many detractors suggest. (Obviously, the
sweetest places to build them are by definition limited, but you can also
build pumped hydro with a very low head, like on some of the Great Lakes
projects, or with a very large head requiring very little water.... you don't
need a nice canyon feature for pumped storage, a big round concrete reservoir
on top of a hill works just fine, too. And with enough volume of water, you
don't even need a hill.)

And I say this as a firm believer in the potential (heh) of the lithium
battery and in Elon Musk. Pumped hydro should not be ignored.

~~~
jgibson
Keep in mind those two solutions are on opposite sides of the world. I found
this [1], which gives the projected Snowy Mountain 2.0 proposal in Australia
at $250/kWh (AUD, presumably).

Regardless, I don't disagree that pumped hydro can still a viable choice in
some places when it comes to large scale, I think South Australia made the
best choice going with battery storage, even if driven from mostly political
reasons.

The SA govt needed to show the federal govt they were capable of holding their
own on their renewable policy, against the federal line of the Snowy Mountain
2.0 pumped hydro. Having something up and going in ~100 days with very few
unknown factors (pour concrete, install batteries, hook up to grid), opposed
to waiting 5-10 years for a solution from the federal government that hasn't
even finished a feasibility study yet, and has so much more risk (geological
survey, environmental survey, new transmission lines [0] etc)

The other advantage of battery storage I see is that it is immensely flexible
for a rapidly changing market. Underprovision? Just buy more. Overprovision?
Truck them somewhere else, lease them to a business with peaky loads, plenty
of other options.

[0] [http://www.illawarramercury.com.au/story/4681519/snowy-
hydro...](http://www.illawarramercury.com.au/story/4681519/snowy-
hydro-20-could-cost-double-initial-2b-estimate/?cs=7) [1]
[https://bravenewclimate.com/2010/04/05/pumped-hydro-
system-c...](https://bravenewclimate.com/2010/04/05/pumped-hydro-system-cost/)

------
mac01021
I wonder how much lower it can get over the next decade.

~~~
ZeroGravitas
The same project published goals last year, for 2030.

2011 goals targetting 2020:

$0.09 per kilowatt hour for residential photovoltaics (PV)

$0.07 per kilowatt hour for commercial PV

$0.06 per kilowatt hour for utility-scale PV

2016 goals for 2030:

$0.05 per kilowatt hour for residential PV

$0.04 per kilowatt hour for commercial PV

$0.03 per kilowatt hour for utility-scale PV

This slightly older piece from 2015 make some projections based on a 16%
learning rate and suggests various large orgs have estimated similar levels:

[http://rameznaam.com/2015/08/10/how-cheap-can-solar-get-
very...](http://rameznaam.com/2015/08/10/how-cheap-can-solar-get-very-cheap-
indeed/)

~~~
ju-st
$0.03 per kWh for utility-scale PV in Dubai, will go online in 2020
([https://pv-magazine-usa.com/2016/11/29/worlds-cheapest-solar...](https://pv-
magazine-usa.com/2016/11/29/worlds-cheapest-solar-power-contract-signed-for-
dubai-mega-project/))

~~~
ZeroGravitas
I believe the Sunshot numbers are specifically about the USA. The amount of
sunshine, cost of finance and installation costs are three big factors that
vary by location, all three of which are probably contributing to that
particular bid, but yes the general trend is looking very good.

------
melling
What’s it going to take before US homeowners start putting solar on their
roofs en masse? With all the power outages in Florida after the hurricane,
rooftop solar would have been useful.

~~~
mac01021
Rooftop solar only helps in scenarios like that if you also have an attached
storage system. You're not going to power your fridge/oven/dryer directly from
the panels.

I would also like to see rooftop solar become widespread in the near future.
But I think for most people to get on board, they'll need to be able to break
even on the investment within something like 3 years.

~~~
ZeroGravitas
Storage makes it better, but even just being able to charge your laptop,
phone, car and run your air-con during the day would be a win.

I don't think most solar installations are designed to operate without a grid
connection though, and even not all powerwall installations can run off grid.

Though I'm not sure that they beat a generator (diesel or connected to your
gas line) if you really anticipate regular grid outages and probably won't for
a while.

~~~
jaclaz
>Storage makes it better, but even just being able to charge your laptop,
phone, car and run your air-con during the day would be a win.

You mean the car that is parked during the day in your office parking lot a
few tens miles away and the laptop and phone that you are carrying with you?

Seriously, without some form of (efficient) storage system, the whole thing
depends on exchanges on the grid.

Off grid - as I see it - is a very nice solution (still with some minimal
storage) for a hut in the woods, where everything is specifically designed for
low power (and where you don't have a dishwasher, a washer, etc.), replacing -
in a more environment friendly way - the noisy generator, but still it remains
something good for youe being there on - say - every other weekend.

Having an el-cheapo (diesel or gasoline) small generator for emergencies is
handy, but only for those hopefully very rare emergencies, the cost for a good
quality (suitable to run often and in several hours stretches) generator and
for the fuel is not competitive with solar (though of course the initial cost
of solar is still higher).

~~~
melling
Everyone seems to be forgetting that you can get paid to transmit your extra
power back to the grid during the day. Air conditioning, for example, is high
during the day. You might not need it at home but someone else will.

~~~
jaclaz
>Everyone seems to be forgetting that you can get paid to transmit your extra
power back to the grid during the day

The idea in my previous post was:

>the whole thing depends on exchanges on the grid.

and anyway we were talking of off-grid setups.

------
nielsbot
Outbrain? Et tu, Ars?

------
codecamper
Get ready for 8c or 9c per kwh, courtesy of Trump's solar tariffs.

Actually, please get ready to fight these tooth & nail.

[https://www.wired.com/story/why-the-us-solar-industry-
doesnt...](https://www.wired.com/story/why-the-us-solar-industry-doesnt-want-
government-protection/)

~~~
crdoconnor
Chinese solar tariffs came in under Obama, not Trump.

It was also pretty clearly done at the behest of the fossil fuel industry and
"greenwashed" by pretending to be done to protect US solar jobs. US solar
_manufacturing_ (as opposed to installation) is a pretty tiny industry with no
political muscle.

The justifications were cringeworthy too. I took a glance at the US trade dept
documents accusing China of protectionism and the first one I saw made
accusations of "free advertising" because Chinese local government promoted a
local solar company on its website.

~~~
codecamper
Sorry, to be clear, the ITC is now considering a case which would bring a
minimum import price to solar cells. Meaning this would be applied to ALL
imports from ALL countries.

------
EGreg
I can still hear many Conservatives saying: "But SOLYNDRA!!" :)

[https://en.m.wikipedia.org/wiki/Energy_subsidies](https://en.m.wikipedia.org/wiki/Energy_subsidies)

~~~
imglorp
$5 trillion/year global fossil subsidies is nothing to sneeze at [1]. And
that's not counting indirect fossil subsidies such as $2T wars on
fossil/defense's behalf.

It suddenly makes a few $20 billion storm cleanups pale by comparison.

[1]
[http://www.sciencedirect.com/science/article/pii/S0305750X16...](http://www.sciencedirect.com/science/article/pii/S0305750X16304867)

