Articles by Gar Lipow

Warning: techno-engineering speak ahead

Amory Lovins is rightfully admired by environmentalists. But nobody is right all the time, and the hydrogen path is one of his few mistakes. He summarizes his argument for hydrogen in Twenty Hydrogen Myths (PDF). More extensive discussion is embedded in his book Winning the Oil Endgame (book-length PDF).

His basic proposal:

Let’s not fetishize size

Many environmentalists are reverse size queens -- "small is beautiful."

When Schumacher wrote the book of that title, he was responding to a real tendency to ignore diseconomies of scale -- a tendency that still exists. Up to a certain point, both organizations and physical plants produce more output for each unit of input as they grown in size. Past that point, costs of gigantism kick in, and efficiency begins to fall instead of rising.

But Schumacher assumed that this point always occurs at small or medium sizes. In fact, there are many cases in which you get economies of scale up to very large sizes indeed.

For example, computer CPUs are still made in giant factories, not neighborhood plants; your computer would cost a whole lot more if that were not the case.

Believe it

A while back I claimed that an all-dispatchable grid would require 75 hours of storage. I have been definitively proven wrong. Nothing like that is required.

In fact, tiny amounts of storage may do the trick if the grid is large enough -- and making the grid large enough is not that expensive. We may already have in place what we need for a completely renewable grid.

The 75-hour figure came from studies of single, isolated wind farms. But as you add wind farms, the odds of two wind farms being down -- or low producers at the same time -- drops.

I came across confirmation by accident: a Vehicle to Grid study (PDF) that evaluated data from eight sites showed that storing just 36 minutes of nameplate capacity would allow the widely dispersed farms to meet a firm power commitment ~90% of the time.

There are tricky steps involved. I am not necessarily advocating a 95%+ wind grid, as there are many ways to generate renewable electricity. But just as coal dominates power production in our current system, I suspect wind will dominate in any future grid. So consider the following a limiting case for wind.

It’s not the key to making renewables work

In his post on the potential of our current grid to support electric cars, John McGrath mentioned V2G in passing.

Electric cars (either hybrids or full EVs) have the potential to be a real-life silver bullet. Anyone who advocates for increased use of renewables is inevitably confronted with the problem of intermittency. With wind, the rule of thumb is that if grid energy supplied by wind grows to more than 25-30%, utilities need to spend prohibitive amounts on "spinning reserve" to even out supply.

Well, a nation driving plug-in hybrids makes for a spinning reserve of amazing proportions according to one estimate (PDF), the U.S. fleet would power the U.S. electrical grid seven times over.

What these estimates neglect is the capital costs of the batteries themselves. The assumption seems to be that since car owners have the batteries anyway, the economics can be calculated based on operating costs -- electricity and inconvenience.