Continue Reading: http://www.nytimes.com/2012/01/03/b...-for-use-after-dark.html?partner=yahoofinance
Since the lion's share of energy use is during the daytime the "problem" of solar is a mole-hill. Night-time energy use can be sourced from wind. As solar production ramps up some time-shifting will be required but I think the obvious solution is sending the fraction not used locally a couple hours east of west. If the US can build a decent national grid, "problems" solved. EVs are a cute side-show, infrastructure is paramount
Peak energy use occurs after sundown. Good storage is an absolute necessity to making large-scale solar part of the US grid.
I like the idea of solar. Great during the day and the west of a Country like the US could perhaps power the east as it gets dark. Or redundant EV power supplies can be built locally to store power for use in the evening. Significantly less power is required at night, esp when we're mostly all in bed. Natural gas power stations can be on standby for when required and nuclear could provide a base level/load at a minimal level. Exciting times and the possibilities are endless.
Just for info, the storage problem is more for cloudy days. Past solar plants (e.g. Kramer's Junction) had contractual obligations to provide full power every day, rain or shine to the paying utilities. Those plants had a backup Natural Gas system to meet those contractual requirements. I suspect that the same contractual requirements will be on these solar plants, requiring a storage system not necessarily designed to provide 24 hour power, but provide reliable daily peaking power, rain or shine.
That is a huge if - there is no national grid right now, and what exists seems to be woefully strung together - it is amazing that there have not been more issues like the east coast blackout from 5 or 6 years back. While it would be expensive a national grid would be a huge advancement for the country. Isn't a national DC grid part of the Pickins Plan? To me it makes a heck of a lot of sense more than converting long haul trucks to CNG.
Certain aspects of our grid are in desperate need of improvement. Most of the problem is the economic situation of those that would pay for grid improvements don't get the payback from doing so. (Would you work for free....even if your job was saving lives?) This requires changing are regulations and utility payment structures to make an efficient grid payback those who would improve it, not putting the US government (and associated "Grid Czar") in charge.
You guys are missing the obvious,, EVs and plug in hybrids. These cars can both by and sell to the grid, buying when the price is cheaper, selling back when the price is high, providing peak load capacity, to reduce idle spinning capacity. In the US' we build ~15 million cars ER year. If 10% were EVs , in 10 years we would have ~15 million batteries connected to the grid, all providing the big battery to allow PV and wind to be more useful at times of no sun and no wind. Icarus
NREL's working on that very idea. It's not big enough to solve the entire energy storage problem, but it's big enough to matter.
I am personally for CAES since it can be used to store any type of energy not just solar, but haven't looked at efficiencies. [ame=http://en.wikipedia.org/wiki/Compressed_air_energy_storage]Compressed air energy storage - Wikipedia, the free encyclopedia[/ame]
Compressed air can be tricky. It's used to increase the efficiency of fuel-burning turbines (which makes it guilty by association for some people) and it usually depends on having a pre-existing, mostly air-tight underground cavity to pump in & out of.
Where are the storage devices for Nuclear power plants? Everyone seems to concentrate on Solar needing storage, but nuclear plants need to be down for months to refuel, it makes solar plants look reliable. Remember that it is length of down time that determines the required size of the storage facility. And that inevitable losses multiple over time. While it nice to think about the time when we will need storage for solar energy, I don't think that time is near.
You know the answer, so I'm a little unsure of what point you are after. Most of the time, it's the other power plants on the site that make up for a scheduled outage. For example, the Florida Crystal River nuclear plant is down hard, but the Crystal River coal plants there are providing the power. As mentioned earlier, the storage at solar and potentially wind plants are not necessarily for long time storage (weeks), but for the short duration (hours or days) storage capacities necessary for contractual requirements from the purchasing utilities. It most definitely is not to serve for a plant outage, especially a scheduled plant outage.