By Jan TenBruggencate
Advertiser Columnist

Energy efficiency, renewable energy, energy conservation — all the same sort of stuff?

Absolutely not, argue those deeply involved with the energy movement.

The Hawai'i Legislature is discussing that issue with regard to the state's tax credits for energy projects.

The tax credits that expire this year are granted for construction of such things as solar water heaters, windmills, heat pumps, and air-conditioning systems that make ice when power rates are cheap and use the ice to cool buildings when rates are high.

But some legislators say those are very different things. Solar systems and windmills are about renewable energy; there's no fossil fuel involved in these systems. A heat pump is a more energy-efficient way of managing heat and cold, but not one that replaces fossil fuel-generated power. And ice-storage air conditioning is a load-management technology. It aims to use electricity when utilities have lots of extra power because demand is low, and to avoid using power when demand is high. It still uses lots of electricity.

Is the terminology important? One reader insists it is. He sent this note in response to a recent story: "I was surprised that you used the term conservation, rather than efficiency, to describe 'ways to accomplish everything we need with far less energy.' "

He was surprised, in part, because one of the icons of energy efficiency, Rocky Mountain Institute energy guru Amory Lovins, says they are so different.

"There is a stark difference between efficiency and conservation. Conservation is a change in behavior based on the attitude, 'Do less to use less.' Efficiency is the application of technologies and best practices to eliminate waste based on the attitude, 'Do the same or more with less,' " Lovins wrote.

It's not clear to me that the difference is always so stark.

If you install a solar water heater and a flow restrictor on the shower head, you can take longer showers using less water and no electricity, blending conservation and efficiency, as well as using renewable energy.

Lovins, one of the great thinkers in responding to the world energy crisis, would not have us taking fewer showers or living in dim light — a kind of Luddite conservation effort. He prefers the gleaming world of new invention, super efficiency and cutting-edge technology. For instance, Lovins has a high-tech Hypercar design that he hopes will get 90 miles per gallon of gasoline, or 200 mpg of hydrogen. Drive the same or more, use less.

The terminology, thus, is important, but to paraphrase a character in Lewis Carroll's "Through the Looking Glass": The words mean what you choose them to mean.

Jan TenBruggencate is The Advertiser's Kaua'i bureau chief and its science and environment writer. Contact him at (808) 245-3074 or e-mail jant@honoluluadvertiser.com.