Friday 24 Sep 2021 | 22:38 | SYDNEY
Friday 24 Sep 2021 | 22:38 | SYDNEY

Why energy efficiency matters


Sam Roggeveen


7 March 2011 15:46

We've discussed previously on The Interpreter the seemingly inescapable conundrum at the heart of global efforts to reduce carbon emissions through technology: if we make power generation more efficient, won't that just create an incentive to use more of it'

To put this in everyday terms, the idea behind the Toyota Prius is that its fuel-sipping hybrid engine will reduce emissions. But in practical terms, making a car more fuel-efficient is no different to reducing the price of fuel. Yet nobody believes that making petrol cheaper is the right path towards reducing transport emissions. On the contrary, increasing the price of fuel (through a carbon tax or something like it) is considered the right thing to do.

It's an example of what's known as the Jevons Paradox, and it's at work in Sweden:

Swedes love to keep statistics on green car sales, but there's a new statistic that doesn't reflect so well on squeaky-green Sweden. People rushed to buy green cars (there was a generous subsidy) and they are now driving them more. Emissions from the transport segment rose by 100,000 tons last year in Sweden. Trafikverket, the Swedish Tranport Agency (STA), reported that while purchases of efficient and greener cars decreased carbon dioxide emissions on a per car basis (from 164 to 151 grams of CO2 equivalent per kilometer driven), people's increased driving caused emissions to rise.

Theoretically, at least, a fuel tax should be able to compensate for the Jevons Paradox, with the tax getting increasingly higher as fuel efficiency improves. There are also limits to how much energy people want to consume, no matter how cheap it is. Even if petrol was free, for instance, it's unlikely many people would be tempted into four-hour daily commutes. And when washing machines become more efficient, consumers aren't suddenly tempted to do a lot more washing.

In other words, efficiency is not necessarily self-defeating. So let the race for the first affordable electric car continue! (Above, the Renault Twizy, set to be launched in Europe this year and starting at €6,900. Photo by Asier Llaguno.)