Cool Stuff: Large-scale Energy Storage

Power generation and distribution systems suffer from two expensive characteristics:

  • Inexpensive power sources aren’t always near users.
  • Generation capacity doesn’t always line up with power demand. For example, power suppliers have to meet peak demand that may consume several times the average for just a few hours a day.

There are a number of solutions to the first problem. High-voltage transmission lines can carry electricity long distances, but there are losses and expenses to transporting power even in that form. Rather than generate electricity at the power source, sometimes it’s more cost-effective to move the power source to the demand: So we have natural gas pipelines and coal railways spanning continents to deliver fuel to generators closer to users. Have a cheap power source that can’t be moved around or attached to a high-voltage grid (say, geothermal wells in Iceland)? Power can be exported in the form of energy-intensive commodities, like refined aluminum.

To solve the second “peak demand” problem most power systems rely on flexible but expensive natural gas generators to supplement their baseload supplies. But it would be better if they could run their cost-effective power plants at a more consistent level and somehow store the extra energy generated during off-peak hours to release during peak hours. When you’re talking about hundreds of megawatt-hours chemical batteries are not a realistic solution. Some utilities are investigating flywheel arrays, but at this point the capacity and cost-effectiveness of those are limited.

Two clever solutions to the problem are compressed air energy storage (CAES) and pumped hydro storage (PHS). PHS depends on being near a water reservoir: It’s basically a hydroelectric dam that is filled during off-peak hours by pumping water up into it and run during on-peak hours by draining water through turbines. The EU has about 40GW of PHS capacity and the U.S. has about 20GW. As with PHS, CAES depends on geological circumstances. Presently there’s only one plant in the U.S. (at McIntosh, Alabama) running CAES. Thanks to its location near an underground salt dome it has a 19 million cubic foot cavern that the plant can pressurize up to 1100psi. When full this CAES reservoir can run a 110MW generator for 26 hours straight. (Source: Power Magazine.)

QOTD: Public Unions

Governor Tim Pawlenty in today’s WSJ:

The moral case for unions—protecting working families from exploitation—does not apply to public employment. Government employees today are among the most protected, well-paid employees in the country. Ironically, public-sector unions have become the exploiters, and working families once again need someone to stand up for them.

An editorial provides supporting information:

Twelve states including North Carolina and Virginia don’t allow government workers collective bargaining rights, and another 12 allow it only for some unions. These states by and large have managed to hold down their pension liabilities better than have those where public employee unions essentially run the government—see Illinois, New Jersey and California.

Lazy Law Update: IRS Edition

I have previously described the problem of selective enforcement of a byzantine legal code. Today the Libertarian Party alerts us to the federal government’s intention to imprison Wesley Snipes for three years for conviction on misdemeanor charges of ‘willful failure to file an income tax return.’

Why is a failure to file a tax return a criminal non-act? Should people ever be sent to prison for not doing something? If the IRS wants to come after Snipes and take his money, they have power to do that. Who does it help to send the man to prison?

The federal tax code also allows for “selective enforcement,” to put it mildly. Why is it that Wesley Snipes gets a prison sentence, but known tax cheat Tim Geithner gets promoted to Secretary of the Treasury? Maybe Tim should be Wesley’s cellmate. Throw tax cheat politician Charlie Rangel in the slammer too for good measure.