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I've thought about adding solar to my home and can't see any reason why I should even consider a battery for storage. I'm in Texas and so I get plenty of sun and my peak energy demand happens to coincide with that sunlight (due to HVAC). Why should I worry about a complete solution?
The sun goes down at night
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One weird thought I had the other day: high voltage DC transmission lines are getting more popular. I wonder if it would be economical for a high voltage DC line to form a loop around the entire planet, so that the load can follow the sun through a complete cycle.
This has terrifying geopolitical implications, so probably no-one will want to depend on it anytime soon.
The true price of solar is the price to produce reliable, continuous energy. That requires something to smooth out the signal and store the energy, most probably a battery. The solar + battery price is also going down, though not as fast as the solar only piece. But that's the metric we should be following. When that hits $30 per MWh, it'll be game over.
There's "baseload power" (coal, nuclear, wind, solar is really good for this), and there's "Peaker power" (natural gas and hydro are really good for this).
Hydro is super-simple. Just block the water if you don't need energy, and unblock it when you need energy. Ditto with Natural Gas, which can spin up / spin down arbitrarily.
Solar, Nuclear, and Wind generate power on their own schedule and can't really be bothered. But you use OTHER forms of energy when the sun stops shining.
Natural gas is expensive to run 100% of the time. But if you can run Natural gas only 20% of the time, then you're still saving money.
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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…
I think the key is that we can start to develop infrastructure just fine on lithium cells, and it might even accelerate the development of more efficient alternatives develop because it proves the market to investors.
See CAES storage (Texas) and Pumped Hydro energy storage (https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta...)
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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…
One weird thought I had the other day: high voltage DC transmission lines are getting more popular. I wonder if it would be economical for a high voltage DC line to form a loop around the entire planet, so that the load can follow the sun through a complete cycle.
http://www.sciencemag.org/news/2016/01/better-power-lines-wo...
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Not entirely. About 10GW of solar capacity would cover the entire air conditioning load peak for California[1] That's when power prices are the highest, and it doesn't need energy storage. Pretty soon, most air conditioning load will be on solar power. [1] http://www.caiso.com/TodaysOutlook/Pages/default.aspx
But you do need storage and/or backup providers because not having air-conditioning run on cloudy days is not an option.
True, you still need an alternative source of energy in those cases. But realistically, cloudy days reduces the sun, which usually leads to lower temperatures.
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Personally, I think that cold-energy storage (aka: run air-conditioners on overdrive to chill water. Then use chilled-water to cool your house) is the ideal.
It turns out that a vat of 480 Gallons of cold-water has a lot of cooling potential. Chill the water to 40F and you can cool down homes for hours using fans alone. With proper compressors and such, you are like 95%+ efficient.
Your failure mechanism is the probability that your vat of water begins to leak its cold air. Certainly a problem, but way simpler and less of a problem than explosive Li-Ion batteries.
It is my understanding that we are already past or very near a point of no return w.r.t greenhouse gas emissions and global warming. Talk of peak power and renewable excess leads to discussion about the need to store that excess. Could we also expend that energy to do something like scrub CO2? Is this even feasible at a scale that could make a difference?
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In my experience, the perception that "solar isn't for everybody", especially when using housing examples, is fooled by hidden assumptions that were made during the time. Consider the situation in 1950 when you are building a house, you can double or triple the cost of home construction by insulating it so that the net energy needed to heat or cool it is minimal, or you throw a oil burner in the basement which is bur…
> That gets you houses in the New Mexico desert that need no air conditioning (air cooling) and churches and office buildings in the northeast that need no additional heating. Do you have a source for your NM desert example? I'm doubtful you can keep a desert home cool with just airflow.
I've visited a couple of these places, they are pretty neat.
It is my understanding that we are already past or very near a point of no return w.r.t greenhouse gas emissions and global warming. Talk of peak power and renewable excess leads to discussion about the need to store that excess. Could we also expend that energy to do something like scrub CO2? Is this even feasible at a scale that could make a difference?
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This comment gets made in every single solar article put on HN. The true price of solar is what the market is willing to pay for it. If the solar was ruining the grid or was way more expensive than what it seems, we would not keep seeing solar installed at this pace and at these costs. We need to get out of the mindset that all power generators need to produce a steady amount of power 24/7. A flexible grid made of ma…
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.