241–250 of 352 posts
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This has terrifying geopolitical implications, so probably no-one will want to depend on it anytime soon.
It's no different than data links, which have mostly worked without political interference.
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I wouldn't bet on batteries, or at least conventional batteries, being the long term solution. There's interesting work being done with air pressure storage, flow batteries (the largest batteries currently under construction are mostly flow batteries in the 500MWh-1GWh range, though the technology is still in its infancy), and big scary vacuum flywheels. All of these are far less developed than lithium ion cells, but…
Batteries are pretty convenient though. They don't have any moving parts and can supply electricity on demand. Not all lithium batteries are created equal in terms of longevity. A traditional lithium manganese battery might have 500 cycles in it before hitting 80% capacity. A lithium titanate [1] battery might be closer to 5000 cycles. A battery could be designed for long term usage and thus lower the long term cost,…
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That's what's generally happening. It's a bit of a limiting factor, though. As you have more and more renewable, you need more and more gas plants which mostly sit around doing nothing, which isn't free. There's also the opposite problem, particularly in the case of wind turbines; if you have enough, then your base-load (ie coal, nuclear, hydro) plus renewable may sometimes exceed demand. This happens from time to ti…
> As you have more and more renewable, you need more and more gas plants This is only true if the load on the grid is growing. In North America, it is not. Otherwise, you already have enough dispatchable generation available when the sun isn't shining or the wind isn't blowing.
The article I saw the other day showed growth of 4.5% (comparing Q1 2017 with Q1 2018)
Surely that growth in production is matched by a growth in load?
https://renewablesnow.com/news/wind-solar-farms-produce-10-o...
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Online calculators over-estimate costs for large systems. You can find newer installers who are more willing to negotiate prices, and play them off each other. I negotiated one company down from ~$3.5/W to $2.30/W (before 30% credit) on my large residential system - and these weren't budget panels either (Sunpower E20). If you do the discounted cash flow calculation of solar, at $2.3/W, electricity costs you around 5…
I think your numbers are pretty optimistic. You're neglecting depreciation for one. Panels have a lifetime in the range of 20-30 years, inverters have a lifetime in the range of 10 years. 4% is also an optimistic interest rate for a loan that lasts the lifetime of the system. You may be able to get that for a ~5 year loan, but then you need to include the higher opportunity cost of the money that was used to pay that…
As for the 4% interest rate, which in this case is really a time value of money discount rate, I’m comparing it to mortgage loan amounts (which is pretty much the average consumer's risk free rate of return). I’m assuming the buyer can afford a cash system.
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Not only that. Solar energy production follows the sun, which incidentally is what humans also follow and when they are typically active and using most energy. Hence, solar producing energy when it is actually needed and in most demand (peak energy). This is even more so the case in hotter places that need AC.
Typically peak residential energy use is actually early morning and evening. And those tend to be the worst times for solar. Solar is great for businesses and schools, well basically anything that operates mainly or totally during the day.
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You don't need 1:1 storage for solar production but it is a real problem. Germany and California are both facing the problem of the solar "duck curve", that is, high solar production during the day when demand is low and high electric usage at the end of the day when people get home from work as solar production is tailing off. More than batteries they utilize gas peaker plants, inefficient, dirty and expensive plant…
> You don't need 1:1 storage for solar production... You seem to be referring exclusively to solar photovoltaic. Solar thermal generation has quite a different, evening-friendly, distribution curve.
I haven't followed closely recently but my impression was solar thermal has not delivered as promised. Things like Ivanpah was relying on natural gas more than expected. Is this an accurate impression?
This gives me hope. We really do have both the technology, and the money, to cut our fossil fuel usage to almost zero, right now- and morally, there is no other choice.
> Installed prices are higher for systems at tax-exempt customer sites than at for-profit commercial sites
> Residential new construction offers significant installed price advantages compared to retrofits
> No clear relationship between installer-level pricing and installer volume
> Prices vary considerably across installers
> Installed prices in the United States are higher than in other national PV markets
> Installed price declines have been partially offset by falling state and utility incentives
> Installed prices continued to fall in 2016, albeit at the slowest rate since 2009 [emphasis mine]
> Module-level power electronics have a seemingly small effect on installed prices
> Ground-mounted non-residential systems are generally higher priced than rooftop systems
[1] https://emp.lbl.gov/publications/tracking-sun-10-installed-p...
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The market of grid-level energy storage is already proven to investors and anyone in the utilities industry. See CAES storage (Texas) and Pumped Hydro energy storage ( https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta... )
Some sort of battery based tech that is fairly unconstrained by site requirements, as well as complex construction engineering requirements seems to have much more potential.
CAES in Texas was constructed inside of abandoned mine-shafts. Line the mine-shafts with steel to contain compressed air, and bam, cheap energy storage.
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The USA has lots of lakes and mineshafts. And electrical storage in one area can serve multiple states. Indeed, the Bath County Pumped Hydro plant contributes to the electrical stability of 16 or so states.
A $5 billion project here and there will serve more people and in a wider area. If the USA can take advantage of natural resources, in a sustainable way (it doesn't seem like Bath County's Reservoir is damaging the environment), then it should happen. We know how to make hydro-plants that are safe for Salmon and other wildlife (we need to ensure that future Hydro plants need salmon ladders for example), but as long as environmental concerns are identified and addressed, leveraging our natural resources is the most obvious way forward.
