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The missing link to renewable energy

Or we could just use that excess energy to pump water back up to a reservoir so that at night it could be used via gravity to generate electricity. Potential energy keeps forever, basically.

Although there must certainly be some lost efficiencies due to pumping the water up hill... and then again running the turbines to generate electricity.

Solar thermal power plants concentrate sunlight to targets containing a "working fluid" (EG. silicon oil, high pressure water, molten salt, etc.) This hot working fluid is pumped (or uses a thermal siphon to move it) between the target and a large storage tank. As power is needed, hot working fluid is taken from the hot storage tank, the heat is converted into electricity by a steam or Sterling engine driving a generator, and then the cooled working fluid goes back to the storage tank.

These plants can easily be designed to produce any number of hours of electricity, with no additional input at night or in the event of a very cloudy day. You just have to make the hot fluid storage tank larger. Which is actually better in terms of heat loss, because the volume goes up by the cube while the surface area goes up by the square of the size.

So these plants (which tend to be more efficient that photovoltaic solar cell-based plants) don't really need battery storage to deliver a planned level of power generation.

For wind power and PV solar arrays: Cool Story, Dude!

Ive seen some entrepreneurs plans to do that all along the west coast of Ireland. turning a shedload of valleys into resevoir/generation stations. We have some of the best wind and wave generation porential in the world - main peoblems being lack of existing infrastructure and lack of capital - particularly now.

The sheer volumne of land required would make it cost prohibitive, whereas a bunch of these 40 ft containers would be far less physically intrusive, plus you would be able to store them at any location, rather that building the infrastructure to only suit the geography.

I think this may be a major advance, for many of the reasons expressed by the perfessor. The need for efficient and low-cost storage coupled with instant response time suddenly give alternative electrical generating technologies the competitive boost that they need to compete with the giganto scale dirty and inefficient centralized fossil fuel and nuclear power plants.

One of the most important characteristics of solar power generation is that we get the energy for free in astounding abundance for a third of every day. It is so abundant that a PV array operating at 12% efficiency can come close to economic parity (excluding normally unaccounted embedded costs, like degrading our environment) with the dinosaur technologies. The key is converting this intermittent and slow-produced energy into a fast, concentrated power for our machines.

One point of dispute with his presentation, which I suspect he would not argue with in a broader discussion, was the statement "...we cannot conserve our way out...". In my view, we should make it a cultural priority (moral, ethical, practical, beautiful) to consider conservation first and always. In terms of power production, conservation is a free and permanent source of energy.

I am a conservationist, definitely not a NonCon.

Ahhh....TR/Ardy the efficiencies of the pumped storage are well documented !

From personal experience in the field I can attest you "lose on both ends" of the scheme ! But WTH, its a step up from having the electrical potential you've spent serious bucks to generate evaporate into thin air !

OTOH,, I'm seriously intrigued by the cited presentation. And I like its minimalist approach, too ! >Mech

I am quite familiar with a large scale system involving the tallest mountain in Missouri, Tom Sauk, which had a reservoir built at the top. Water ran down, generating electricity, during the high-use day, then was pumped to the top, during the low use night.