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Giant batteries and cheap solar power are shoving fossil fuels off the grid

sciencemag.org

191–200 of 432 posts

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#191
post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

Can't believe all the comments so far and no one feels the need to justify their opinion with numbers. Drives me nuts.

You are correct, according to National Renewable Energy Lab (NREL), rooftop solar is over twice as expensive as utility scale solar[0]. The NREL estimate is helpful in that it details the components of the cost. And, as you would expect, the hardware and labor costs are lower for utility scale because of, well, scale, but the dominating difference is soft costs (land, marketing, profit, overhead, etc). Its worth noting, soft costs for residential solar are significantly lower elsewhere in the developed world (DE, AU) mainly because permitting and marketing are much easier.

[0] https://www.nrel.gov/news/program/2018/costs-continue-to-dec...

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#192
post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

The financial benefit to the end consumer is that their electricity bill goes down since the panels generate electricity on their own.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#193

Earlier quoted context omitted.

>Plus there are many reasons to install solar, not just financial. The thing that surprised us the most when we installed our home solar system was how much cooler the house was during the summer, just because of how much the air-gapped panels on the roof reduced the heating load on the house. We noticed a significant reduction in our AC bills during the couple of months we had the system installed, but couldn't use…

So it works double as another layer of isolation. Seems obvious but I had not considered that before, interesting.

It's reflection plus air flow. Sunlight is blocked from reaching and warming the roof, while warm air rising at the top of the roof will pull in cooler air from the bottom, leading to surface cooling (sort of an accidental half-assed solar chimney). So, it's a couple of different mechanisms at work.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#194
post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

On the major exchanges, electricity is basically free or in some cases even carries a negative price during the day, so there's no money to be made with solar alone. This will get worse as more people install solar at home.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#195

I know someone who has gone fully off the grid via sailboat and is currently on his way around the world. He converted his sailboat to a hybrid setup (electric engines powered by the same batteries that power his stovetop, refrigerator, etc.). His power sources keeping those batteries charged are solar (1200W) and sail regeneration [0]. He has an 18kw diesel generator as a safety measure. His story is particularly in…

>At this point, I feel like the only reason fossil fuels are used anymore in new projects is inertia Solar might work for boats and trains, but can it work for a plane? What about drones? No renewable energy source can beat gasoline, sans nuclear power (which I think we should be transitioning to, along with the rest of the renewables). MIT built a gas powered drone that lasts 5 days (not minutes!) in the air[1] - th…

How can you still think Nuclear is a good idea after reading that article? If a solar/battery farm is that cheap now, how cheap do you think it will be once you've spent 15 years building a nuclear power station that will either get flooded (rising sea for cooling) or have to be left turned off (fresh water no longer available)?

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#196

Earlier quoted context omitted.

You only need to think of the other things that solar requires in order to see where scale cost might arise - land and infrastructure. Labour is cheap. Solar needs space and it needs a way to export it's electricity to where it's needed, or to where it is stored. Places where space is cheap enough almost universally don't have infrastructure. So large scale solar does come with large capital costs. Contrast to home o…

>Plus there are many reasons to install solar, not just financial. The thing that surprised us the most when we installed our home solar system was how much cooler the house was during the summer, just because of how much the air-gapped panels on the roof reduced the heating load on the house. We noticed a significant reduction in our AC bills during the couple of months we had the system installed, but couldn't use…

I'm eager for architects to incorporate shading into their designs. I love the louvres on the south face of the downtown Phoenix library. I imagine future iterations will put solar panels on those louvres.

Here's a pic with the louvres open.

https://www.archdaily.com/255208/burton-barr-central-library...

Rooftop decks being so popular now, I expect someone clever will eventually add solar panels as shades.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#197
post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

As others have pointed out, wholesale energy cost is only about $0.02 per KW/H, yet retail is usually over $0.2 KW/H. Even if the wholesale cost of energy drops to $0, you are only dropping about 10% of the total cost of energy. Of course, this brings up another interesting question that has been a hot button issue; if power companies are supplying less and less power (since more and more people are getting their own…

It's not that complicated. There are countries in Europe that, in addition to metered price per kWh used also have a fixed price for grid usage. If you feel you're completely self-sufficient and can survive without the grid, you can cut it off and pay nothing. If you use your own power but want to keep the grid connection for backup, you pay for grid access but nothing for power (or get a discount or a refund, or money back if you feed your excess power into the grid.)

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#198
post #84

I’ve always wondered about something, yet have never found anyone discussing it online. So maybe some smart people can help me out: a lot of people install solar on their rooftops. Much of the time this is done with the assumption that it will pay off financially because energy prices are currently at a certain rate and will continue to rise. But here’s my question: If its financially advantageous to install solar on…

Solar farms are spreading & starting to take over a lot of quality farmland in the northern midwest because of the scale/price reasons you suggest.

Wind farms, maybe. I'm not seeing a lot of utility-scale solar (yet) around here. I'm in MN and travel to IA regularly, past the enormous wind farms. A wind farm has negligible impact on farmland use.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#199

Earlier quoted context omitted.

You only need to think of the other things that solar requires in order to see where scale cost might arise - land and infrastructure. Labour is cheap. Solar needs space and it needs a way to export it's electricity to where it's needed, or to where it is stored. Places where space is cheap enough almost universally don't have infrastructure. So large scale solar does come with large capital costs. Contrast to home o…

>Plus there are many reasons to install solar, not just financial. The thing that surprised us the most when we installed our home solar system was how much cooler the house was during the summer, just because of how much the air-gapped panels on the roof reduced the heating load on the house. We noticed a significant reduction in our AC bills during the couple of months we had the system installed, but couldn't use…

I wish I could find the article - there was a report on the effect of installed solar panels and the cost of AC on the (single-family) properties they were on. Would have been in 2016 or 2017, maybe.

But in any case... The overall reduction in energy use was about 5% better than calculated. The article stated that this was discovered to be due to the improved airflow between the roof and panels. Because the panels are installed 40mm-50mm above the roof, they leave effectively a narrow wind tunnel between themselves and the roof surface. This means that with the panels heating up, they cause an increased airflow over the roof.

This increased flow, in addition to the panels heating up instead of the roof, was enough to further reduce the energy required to cool the house down.

You must have been experiencing the same effect.

Re: Giant batteries and cheap solar power are shoving fossil fuels off the grid

#200
post #55

Earlier quoted context omitted.

Why would the landlord spend money on insulation to save you money on your electric bill? There's the problem.

The government should enforce energy efficient building standards and tax those who don’t comply.

They could, but then the costs will just be passed down to the tenants (i.e. increased rent).
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