[ExI] Wind, solar could provide 99.9% of ALL POWER by 2030

[Eugen Leitl]

On Fri, Jan 18, 2013 at 11:32:29AM +0000, BillK wrote:

> The article is attempting to model running the US grid system mainly
> from renewable power sources.

That is a small subset of the problem. The world runs at 16 TW
total, and expected to need 30 TW by 2050.

> I believe the US grid capacity is only about 1TW at present.

The German energy grid already is at 21.9% renewable, 135 TWh total.
Wind was 45 TWh, biomass 41 TWh, photovoltaics 28.5 TWh and
hydro 20.5 TWh.
 
> The study sheds light on what an electric system might look like with
> heavy reliance on renewable energy sources. Wind speeds and sun
> exposure vary with weather and seasons, requiring ways to improve
> reliability. In this study, reliability was achieved by: expanding the
> geographic area of renewable generation, using diverse sources,
> employing storage systems, and for the last few percent of the time,

You only need massive storage at roughly 80%. You need effectively
no storage for 20%.

> burning fossil fuels as a backup.
> 
> The study isn't trying to redesign the whole world. It is trying to
> show that by increasing the use of renewable energy over the next 17
> years it is feasible to run the US grid mostly from wind and sun. As

US, 99% and 17 years is terribly optimistics, even if it would be funded,
which it will not. I see no reason why Germany won't be at 80+% by
2050. 

> Spike points out, cars will become more economical, especially when

Cars don't enter the equation. They're almost irrelevant in terms
of total energy.

> driven by Google.