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Well, considering solar is only available during the day, and wind only when there is sufficient wind, you're making a flawed comparison. You would have to add

Well, considering solar is only available during the day, and wind only when there is sufficient wind, you're making a flawed comparison. You would have to add storage for those sources to compete with nuclear. Now you've got a much lower bar to meet, since we don't really have mass energy storage yet, outside of limited areas where pumped water storage is possible. I expect the cost of using current battery tech to balance solar/wind day to day throughout a typical/ideal month would be huge, let alone however much you would need to cover the possibility of a stretch of overcast days and calm winds. Using nuclear to provide a baseline, and other renewable sources to provide peak power seems to be the way to go for the foreseeable future. I'm not sure how long it will be before we can get to a point where we can use purely non-nuclear renewable sources and storage to cover the baseline power draw, but I don't like the idea of sticking with carbon until then.

toomuchtodo 11y ago
> I expect the cost of using current battery tech to balance solar/wind day to day throughout a typical/ideal month would be huge, let alone however much you would need to cover the possibility of a stretch of overcast days and calm winds. http://www.utilitydive.com/news/hawaii-co-op-solarcity-ink-deal-for-dispatchable-power-from-solar-storage/405408/ http://www.utilitydive.com/news/hawaii-co-op-solarcity-ink-d... 14.5 cents/kwh is huge? And that's with existing battery costs, not taking into account Tesla's Gigafactory ramping up. "The dispatchable solar plant has a 52 MWh battery system that will store energy generated during the day and allow it to feed up to 13 MW of electricity back onto the grid during the evening peak. Under the 20-year power contract, KIUC will pay SolarCity 14.5 cents/kWh, less than the cost of conventional generation in Hawaii, and slightly more than the cost of power from the co-op's other exisiting solar farms."
- bryondowd 11y ago
  > The goal of the new solar-plus-storage facility, KIUC said, is to "'shave' the amount of conventional power generation needed to meet the evening peak, which lasts from 5 p.m. to 10 p.m." So, this is exactly what I said solar is good for, balancing out a bit of peak load, with no significant impact on the baseline. Not likely to impact Hawaii's around 88% carbon based energy production. It's one thing to install enough batteries to shift 13 MW of electricity by a few hours. It's another thing entirely to generate and store enough power to completely remove carbon sources. According to that source, Hawaii has a total capacity of 2.3GW. As far as I'm aware, nobody is even considering that as a near-term possibility for stored renewables. Also note that Hawaii is probably one of the better locations for solar, and things get grim the more northerly or overcast your area is. Also, those batteries store 52MWh, the Gigafactory will have an annual output of batteries with total capacity in the tens of GWhs, while Hawaii uses about 10TWh annually, which is over 27 GWh per day average. I can't find a source for how much of that would be used at various times of day, and unsure of the math for how much battery capacity would be needed to take variable sunlight throughout the day and make it last overnight to the next morning, but I expect you're at leas looking at two orders of magnitude larger than the project you linked. And that doesn't give you much of a buffer in case of a storm blocking out the solar power for even a day, which admittedly is less of a problem in Hawaii than elsewhere. You've still got to either provide enough battery power to hold out until generation exceeds consumption again, or you need enough solar panels that you can generate all the power you need even on cloudy days, and simply disable a large portion of them when it is sunny and the batteries are full. Either way, you'd need every battery the Gigafactory produced for anywhere from a year to a decade, just to maintain reliable power in Hawaii alone. That would be an insane upfront cost without even factoring in solar panels. And those batteries need to be replaced as they lose capacity, so you have to divide that cost over a finite time. Source: http://energy.hawaii.gov/wp-content/uploads/2011/10/EnergyFactsFigures_Jan2013.pdf http://energy.hawaii.gov/wp-content/uploads/2011/10/EnergyFa...

toomuchtodo 11y ago

> I expect the cost of using current battery tech to balance solar/wind day to day throughout a typical/ideal month would be huge, let alone however much you would need to cover the possibility of a stretch of overcast days and calm winds. http://www.utilitydive.com/news/hawaii-co-op-solarcity-ink-deal-for-dispatchable-power-from-solar-storage/405408/ http://www.utilitydive.com/news/hawaii-co-op-solarcity-ink-d... 14.5 cents/kwh is huge? And that's with existing battery costs, not taking into account Tesla's Gigafactory ramping up. "The dispatchable solar plant has a 52 MWh battery system that will store energy generated during the day and allow it to feed up to 13 MW of electricity back onto the grid during the evening peak. Under the 20-year power contract, KIUC will pay SolarCity 14.5 cents/kWh, less than the cost of conventional generation in Hawaii, and slightly more than the cost of power from the co-op's other exisiting solar farms."

bryondowd 11y ago
> The goal of the new solar-plus-storage facility, KIUC said, is to "'shave' the amount of conventional power generation needed to meet the evening peak, which lasts from 5 p.m. to 10 p.m." So, this is exactly what I said solar is good for, balancing out a bit of peak load, with no significant impact on the baseline. Not likely to impact Hawaii's around 88% carbon based energy production. It's one thing to install enough batteries to shift 13 MW of electricity by a few hours. It's another thing entirely to generate and store enough power to completely remove carbon sources. According to that source, Hawaii has a total capacity of 2.3GW. As far as I'm aware, nobody is even considering that as a near-term possibility for stored renewables. Also note that Hawaii is probably one of the better locations for solar, and things get grim the more northerly or overcast your area is. Also, those batteries store 52MWh, the Gigafactory will have an annual output of batteries with total capacity in the tens of GWhs, while Hawaii uses about 10TWh annually, which is over 27 GWh per day average. I can't find a source for how much of that would be used at various times of day, and unsure of the math for how much battery capacity would be needed to take variable sunlight throughout the day and make it last overnight to the next morning, but I expect you're at leas looking at two orders of magnitude larger than the project you linked. And that doesn't give you much of a buffer in case of a storm blocking out the solar power for even a day, which admittedly is less of a problem in Hawaii than elsewhere. You've still got to either provide enough battery power to hold out until generation exceeds consumption again, or you need enough solar panels that you can generate all the power you need even on cloudy days, and simply disable a large portion of them when it is sunny and the batteries are full. Either way, you'd need every battery the Gigafactory produced for anywhere from a year to a decade, just to maintain reliable power in Hawaii alone. That would be an insane upfront cost without even factoring in solar panels. And those batteries need to be replaced as they lose capacity, so you have to divide that cost over a finite time. Source: http://energy.hawaii.gov/wp-content/uploads/2011/10/EnergyFactsFigures_Jan2013.pdf http://energy.hawaii.gov/wp-content/uploads/2011/10/EnergyFa...