Question: How Do Electric Cars (Volt, Leaf) Heat Passengers?

Another in our irregular series of answering questions from readers, this one from John Q of Eugene, Oregon:

Question: I was wondering how an electric car provides heat and defrosting. Using batteries to generate the heat will drain them pretty fast. Maybe with the 2011 Chevrolet Volt, the internal combustion engine is run for heat? But what about the battery-only 2011 Nissan Leaf?

Answer: In brief, cabin warmth on cold days is provided via resistance heating, which–as you note–uses a lot of current.

However, the  Chevy Volt offers heated driver and front passenger seats.And the Cold Climate package offered for the Nissan Leaf includes not only heated front seats but a heated steering wheel as well.

Those items turn out to make occupants FEEL warm enough that the
cabin heat may not be necessary, or can be used at lower temperatures.
But simply heating seat surfaces and a steering wheel requires much less
current than heating volumes of air and blowing them around the cabin.

Under some circumstances, especially if the battery pack has
been cold-soaking, the Volt may switch on its engine when started until
the pack has warmed up enough to be in the appropriate operating
temperature range. Then it will switch off again until the pack is
depleted–which is essentially how today’s hybrids work.

The
Leaf, of course, does not have that option. But when either car is
plugged in to recharge, some energy may be diverted to keep the pack at
its ideal operating range–either cooling via fans (Leaf) or liquid
cooling (Volt), or heating via elements inside the pack.
This story originally appeared at Green Car Reports