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Wind and Solar Can Power Most of the United States, Says Study (theguardian.com)
An anonymous reader writes: The Guardian reports of a recent paper, published in the journal Energy and Environmental Science, that helps explain how wind and solar energy can power most of the United States: "The authors analyzed 36 years of hourly weather data (1980-2015) in the U.S. They calculated the available wind and solar power over this time period and also included the electrical demand in the U.S. and its variation throughout the year. With this information, the researchers considered two scenarios. In scenario 1, they imagined wind and solar installations that would be sufficient to supply 100% of the U.S. electrical needs. In the second scenario, the installations would be over-designed; capable of providing 150% of the total U.S. electrical need. But the authors recognize that just because a solar panel or a wind turbine can provide all our energy, it doesn't mean that will happen in reality. It goes back to the prior discussion that sometimes the wind just doesn't blow, and sometimes the sun isn't shining. With these two scenarios, the authors then considered different mixes of power, from all solar to all wind. They also included the effect of aggregation area, that is, what sized regions are used to generate power. Is your power coming from wind and solar in your neighborhood, your city, your state or your region?
The authors found that with 100% power capacity and no mechanism to store energy, a wind-heavy portfolio is best (about 75% wind, 25% solar) and using large aggregate regions is optimal. It is possible to supply about 75-80% of U.S. electrical needs. If the system were designed with excess capacity (the 150% case), the U.S. could meet about 90% of its needs with wind and solar power. The authors modified their study to allow up to 12 hours of US energy storage. They then found that the 100% capacity system fared even better (about 90% of the country's energy) and the optimal balance was now more solar (approximately 70% solar and 30% wind). For the over-capacity system, the authors found that virtually all the country's power needs could be met with wind, solar, and storage."
The authors found that with 100% power capacity and no mechanism to store energy, a wind-heavy portfolio is best (about 75% wind, 25% solar) and using large aggregate regions is optimal. It is possible to supply about 75-80% of U.S. electrical needs. If the system were designed with excess capacity (the 150% case), the U.S. could meet about 90% of its needs with wind and solar power. The authors modified their study to allow up to 12 hours of US energy storage. They then found that the 100% capacity system fared even better (about 90% of the country's energy) and the optimal balance was now more solar (approximately 70% solar and 30% wind). For the over-capacity system, the authors found that virtually all the country's power needs could be met with wind, solar, and storage."
It's a huge capital investment, huge on-going maintenance, outrageously huge decommissioning costs, and the penalty for falling asleep at the wheel (i.e., hiring a few MBAs to improve 'efficiency') is catastrophe. It's also centralized and makes a nice juicy target for terrorism. Oh, and it costs more than solar or wind--once you fully account for all the actual costs. Westinghouse just went out of business (ask South Carolina).
I'm guessing the future [for most of the US] looks like solar roofs with local battery storage, connected to a grid backed by natural gas peaking/backup plants and various other forms of utility power generation and storage.
the beauty of renewables is that they don't need refuelling. New tech is more expensive initially but thats is capital expenditure and wasteful expense in constantly buying fuel, and the renewable output is now cheaper than coal and catching upto gas. To follow your scare scenario, you'd better close all the coal stations now as they are killing off large sections of the poorest with expense and the added killer pollution. Business are now beginning to invest in their own solar as it makes sense.
try following a site like cleantechnica.com or a video channel called fullychargedshow - it'll expand your knowledge of renewables and their costs/benefits
"The hands that help are better far than lips that pray." - Robert Ingersoll (1833-1899)
Exactly. The only real problem to solve before solar and wind can do a 100% replacement is storage. Solar dosent work at night, works half well during heavy overcast or rainy conditions, and can stop if the panels get snowed on (until they are cleared or melt thier way to freedom). Wind power obviously needs wind, too much or little can also be a problem. You can pump water to store electric power, but it requires large volumes of water and expensive equipment. Batteries would be an ideal way, but they are still too expensive. I think Musk has the right idea, if we can use old electric car packs that are near the end of useful life for the needs of a car, the cost per kWh of storage should get quite cheap as electric cars go mainstream. Not only that, but wind solar and on site storage can remove the need for an electrical grid and centralized production, electric power companies are crapping thier grundies over this.