Just as a test, tonight I plugged in the block heater and

I had a block heater in a V6 GMC van I used to drive and I think it drew about 600 watts. Not particularly energy efficient, but at Lake Tahoe or even more so in Canada, it sure is nice to have the heater come on quickly on a winter's morning.

Rick V.

 

The efficiency of a block heater is way more apparent during the winter in places that get extremely cold. The preheated engine will drematically reduce the strain on the starter, and the warmed oil gets flowing much faster, reducing the time that metal parts are not lubed substantially. This leads to longer engine life.

For Frank's experiment, I don't think he's going to see a huge difference.

 

It's a regional thing, out here on the Left Coast, but most of us in Oregon Washington and British Columbia DO receive hydroelectric power.

Time permitting I'll try to determine the cost foar a 1,000-watt block heater boost from Puget Sound Energy. Maybe our colleague in Vancouver can get the same info from BC Hydro.

I'm very interested because I plan to install a block heater next October.

Regards,


Bob

 

i don't actually own a prius, so forgive me if this is dumb. but didn't i read that the prius (04) has a thermal storage tank for coolant that actually keeps it warm for several days so that it's ready to warm up the ICE right away?

doesn't that sort of negate the benefit of the block heater? though i guess the heater is probably still more powerful...

 

Thermos is a good idea for the belly of the market, but cannot compensate for thermal loss in maritime or "rust belt" climatesfrom late September well into April.

Even in Seattle in winter, we get a succession of days just above freezing to not much more than 45 degrees F. for weeks on end. Any wind chill and it's worse. And we DO have our subfreezing days.

This really sucks the heat out of the entire car, not just the ICE block, making the thermos marginal if somewhat helpful.

The block heater makes sense to me in tyhis environment and may be a more economical solution where lower cost hydroelectric therms minimize the net cost to heat the block.

Downstream there may be low cost solar storage unit that can power a block heater, or perhaps a home solar unit for a swimming pool/home heating booster can be co-opted to provide enough current (or heat source) to keep the block a little warmer.

There's always a way...


Bob

 

I live in california so a block heater isn't in my future but if I lived in a cold climate I think it could be helpful.

If wouldn't necessarily save too much gas, but would reduce engine wear and emissions.

The cat warmer thermos is useful, but if you think about it there's no way it can heat up the whole engine back to operating temperature. Even if the thermos worked perfectly and put the fluids back at the normal operating engine temperature, the heat capacity of the rest of the engine would cool them down very quickly. The issue is that the heat capacity of the fluids in the thermos is much less than the heat capacity of the engine as a whole, just because the engine as a whole is much larger and more massive.

So right when the hot fluid from the thermos hits the engine, it's heat will start getting dissipated into the cold engine and cooling system. Engines are designed to dissipate the heat of the internal components quickly.

Just to make up some numbers, lets say that overnight the engine reaches a temperature of -25 degrees F, while the thermos fluid stays at 200 degrees (I have no idea if this is right). If the heat capacity of the engine is lets say eight times that of the fluid, then you wind up with an engine temperature of about zero degrees after the fluid goes back in and the heat has a chance to even out within the engine.

But if you use an engine heater, you can bring the engine up to a much warmer temperature (perhaps 50 or even 100 degrees).

Since cold starts are by far the main emissions problem and wear issue for engines, using an engine heater could significantly lower emissions and make the engine last longer, paying for itself.

 

And therefore the thermos is an anti-pollution device which has little or no effect on how quickly you get heat for the cab.

However, the Prius provides heat to the cab in about half the time of my old Civic. Not until about 15 blow zero (F) does it become too painfully cold to drive without pre-heating.

Block heaters are normally used on cars that just won't start otherwise. But the Prius doesn't even start like other cars, so this is not an issue.