by Jeremy Mahowald, manager of energy management and conservation
If you live up here, chances are you have a block heater on your car or truck. Many of us know by experience that a frozen engine can be hard to start and takes a long time to warm up. Using the block heater makes for easier starting and less time scraping. For most people, that’s about where the knowledge stops.
Many independent studies have been done, along with the US Dept of Energy, and Natural Resources Canada, giving us more insight and info into block heaters and how they should be used:
Using a block heater saves on the wear and tear of your engine.
Canadian studies have show that block heaters can improve fuel economy by as much as 10%.
A cold engine increases emissions of CO and NOx by 50 to 100 times in the first minute versus a warmed one, which increases the danger of asphyxiation if you start it in your garage. It also increases urban smog.
You should plug in your vehicle when the temp is 20°F or colder.
Do not plug in your heater for more than 2 hours, anything more is a waste of energy. A timer is the best way to regulate this.
Block heaters really have a large range in size and can vary from 400 W up to 2,000 W per unit. Typically on cars and pickups, you’ll see 400 – 800 W and the larger units are on bigger diesel vehicles and tractors. My pickup block heater draws 600 W.
If I plug my pickup in at 10 at night and leave at 7 AM, it will cost me $0.54 per night at $0.10/kWh, where if I use a timer that comes on at 5 AM and shuts off at 7 AM, it will only cost me $0.12 per night.
We know of many members who keep their tractors plugged in 24 hours per day or every hour they are not in use in the winter. If the tractor has a 1,500 W block heater at $0.11/kWh, that is almost $4/day. A timer could keep this down to $0.50/day or less.
Using your block heater on a timer saves energy, gas, and the life of your vehicle. And it is FAR cheaper and more efficient alternative than heating your garage.