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Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

cleantechnica.com

41–50 of 257 posts

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#41
I think the future will be robust national/international grids, with a mixture of storage options (batteries/pumped hydro) to smooth out the intermittent nature of wind and solar.

Cynics always talk about the amount of energy storage required for solar as if you need to store 24 hours of energy for solar/wind to be viable.

I'd like to see numbers on having 1 hour of storage for peak demand, a robust national grid, and appropriately provisioned and placed solar and wind, taking the duck curve into consideration.

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#42
post #2

This is good to hear. I assume location must play a large part in this? Solar must be more cost-effective in, say, the Mojave desert, than it is in Alaska. I sometimes wonder if the widespread adoption of solar is going to have an environmental impact that isn't immediately apparent. Every solar panel you put on the ground is going to take up solar energy that could otherwise be absorbed by a plant, which in turn mea…

One possibility is to use farmland or grazing land. You can pick crops that do better in part shade and then place solar panels over them. If done right it could have a beneficial effect on crop growth while at the same time earning extra money.

But then harvesting would be significantly harder, no? At least in the way I imagine this.

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#43
post #7

Earlier quoted context omitted.

It's a little hard to predict how the price of battery storage will change as demand for it increases by orders of magnitude, and also how energy usage patterns will change as the relative cost of nighttime energy usage goes up. I've explored these themes in the past in a number of notes. https://dercuano.github.io/topics/solar.html and in particular https://dercuano.github.io/notes/energy-storage-efficiency.h... , h…

...how energy usage patterns will change as the relative cost of nighttime energy usage goes up. My fondest dream is that they'll stop dotting the countryside with those ridiculous pole-mounted "security" lights, and we'll be able to experience nighttime again.

I think our best hope for this working out is from the (very slowly) growing view of light pollution as the actual _pollution_ that it is.

I would absolutely love this, but I still find it hard to imagine this changing in any significant way in the next 25 years.

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#44
post #31

Earlier quoted context omitted.

People use way too much power for battery storage to be viable. The average household consumes 28.9kwh in a day (in 2017), which is way more than rooftop solar can provide. Maybe when we have smaller houses and don't have a bajillion devices plugged in all the time.

> The average household consumes 28.9kwh in a day Maybe in the USA. > which is way more than rooftop solar can provide. Maybe in your part of the world this is true, but it is not unrealistic in many places. Also, why are you limiting your thinking to rooftop solar?

The article is referring to the prices in the US.

When land is at a premium, most people aren't going to cover their yard with solar panels. . Rooftop is already generally accepted.

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#45
post #42

Earlier quoted context omitted.

One possibility is to use farmland or grazing land. You can pick crops that do better in part shade and then place solar panels over them. If done right it could have a beneficial effect on crop growth while at the same time earning extra money.

But then harvesting would be significantly harder, no? At least in the way I imagine this.

I'm not sure but certainly it would depend on the crop as different harvesting methods are used for different crops. For example, panels could be built so cows can graze under them or for handpicked crops so that people can walk under them.

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#46
post #6

Earlier quoted context omitted.

> I assume location must play a large part in this? Solar must be more cost-effective in, say, the Mojave desert, than it is in Alaska. Yes, each peak kilowatt of utility-scale solar produces about 240 watts average in Arizona, 140 in Maine, and 100 in Germany ("capacity factors" of 24%, 14%, and 10%). I assume the number for Alaska would be even lower. > Every solar panel you put on the ground is going to take up so…

> it will reflect less heat back into space than the plant or bare dirt would, locally raising the temperature I'm not sure this checks out... the light gets absorbed, but the energy doesn't get turned into heat, it gets turned into electricity. If anything, where it's covering up concrete or asphalt it should reduce the conversion of sunlight to local heat.

Research from 2016: https://phys.org/news/2016-11-solar-island-effect-large-scal...

Tl;dr solar raises temps slightly in the vicinity of the panels.

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#47
post #24

Earlier quoted context omitted.

It's relatively high, the problem is that building new dams is an environmental disaster, and existing dams are two orders of magnitude below needed capacity. Also, hydro dams kill a lot of people when they have accidents.

Do you have to dam a river to store energy in this way? Can they just build water towers that pull water from underground up into a tank and release it via gravity to generate power when needed?

Not enough energy. Hydropower reservoirs are typically many square kilometers of water surface, depth > 10 meters on average and a height differential on the order of 100 meters or more. Vary parameters according to geography, but it's not something that can be built without using geology for support.

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#48

Earlier quoted context omitted.

People use way too much power for battery storage to be viable. The average household consumes 28.9kwh in a day (in 2017), which is way more than rooftop solar can provide. Maybe when we have smaller houses and don't have a bajillion devices plugged in all the time.

Most people will have a big battery in their garage capable of powering their house for days pretty soon.

Unless battery prices drastically drop, 2 days of power is 60kwh (quoting earlier figure), even if batteries were $100/kwh, that's $6000 in batteries (or ~$9 if you're on grid)

edit: bad math, had $60k

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#49
post #2

This is good to hear. I assume location must play a large part in this? Solar must be more cost-effective in, say, the Mojave desert, than it is in Alaska. I sometimes wonder if the widespread adoption of solar is going to have an environmental impact that isn't immediately apparent. Every solar panel you put on the ground is going to take up solar energy that could otherwise be absorbed by a plant, which in turn mea…

> Solar must be more cost-effective in, say, the Mojave desert, than it is in Alaska.

I don't think this was your intention, but this reminded me of something I see in so many of these conversations.

In discussions about solar (and electric cars) there are always people who say "well this won't work in situation X", with an unsaid implication of "this is not the solution".

It is unlikely that we will find a single solution that will be a good fit for all situations. Instead we will have many tools in our belt and apply accordingly.

I know that you used alaska as an extreme, perhaps they will never get off fossil fuels. But alaska is a tiny population overall. Its the main population centers that we need to worry about, not the extremes that are hand picked to be difficult.

Re: Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

#50
post #31

Earlier quoted context omitted.

People use way too much power for battery storage to be viable. The average household consumes 28.9kwh in a day (in 2017), which is way more than rooftop solar can provide. Maybe when we have smaller houses and don't have a bajillion devices plugged in all the time.

> The average household consumes 28.9kwh in a day Maybe in the USA. > which is way more than rooftop solar can provide. Maybe in your part of the world this is true, but it is not unrealistic in many places. Also, why are you limiting your thinking to rooftop solar?

Probably in a lot of countries in the future. One common reason countries have lower average household electricity consumption is the widespread use of non-electric heating, and there's been a huge push to switch to electric heating for environmental reasons.
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