Michael Davenport recently argued in the Vancouver Sun that people with gas heaters and renewable-source electricity should use incandescent light bulbs. This would provide extra heat, reducing their gas consumption and overall greenhouse gas emissions.

This is fine for a strictly local analysis, and Davenport explicitly intends it as such. But he neglects to consider BC’s electricity exports. If we switch to efficient bulbs, that means we use less hydro power for our light bulbs and more natural gas for heat. Then we can export more hydro power to Alberta, and they can use less natural gas for their light bulbs. Does this reduce greenhouse gasses? Yes: burning natural gas directly for heat involves fewer conversion losses than a gas-fueled power plant. This is why Canada-wide calculations show an overall environmental gain from fluorescent bulbs, as Davenport notes in his article.

Ironically, this counter-argument strengthens Davenport’s underlying point: mandating technology choices has surprising results. Thus, this kind of regulation often doesn’t achieve the environmental benefits we hope for. A better policy is to penalize pollution itself, as with a carbon tax. This more general and flexible policy will improve the overall societal mix of heating technologies: gas powered heaters, hydro powered light bulbs, and wool sweaters.