Because electricity is expensive per BTU compared to other fuels. Or historically it has been.
Now a heat pump exceeds 100% efficiency (wrap your head around THAT) but suffers below about 35 degrees. Heat pumps are used in water heaters, clothes dryers and EV auto AC systems.
My plug-in hybrid also uses a heat pump. In comparison with my previous IC-only vehicle, I find that I have to set the climate control to 72 in the winter, instead of 70, but with a setting of 72, it is very comfortable.
Heat pumps make great sense in a hybrid. ICE engine heat is always available to boost that 10 degree ambient up to something the heat pump can use.
I like the electric AC compressors becoming available, too. Makes vintage car air conditioning easier⊠and hidden! Same for electric power steering!
Newer heat pumps work fine to below freezing. There are some new homes not too far from me and their heating and cooling system is a heat pump. No backup.
Apparently all the EVs are using heat pumps now. The COP of a heat pump is around 4 if I recall correctly. That means 1kW of electricity makes 4kW of heat. With greater temperature differences in very cold weather the COP should drop though.
It probably takes what maybe 4kW to heat a car? A hair dryer or space heater is 1.5kW.
I donât think the there is a significant amount of wasted heat generated in an EV during normal driving. Lithium Ion is nearly 100% efficient. The motors would be about 90% efficient so you might be able to capture 1kW, but the temperature probably wouldnât be hot enough to use directly. Thatâs only 1/4 of the way to comfortable heating in a car.
Some years ago, I thought about buying a used CitiCar. This was an EV manufactured in the late 1970s. I was going to experiment to see how much I could save using the CitiCar as an around town vehicle. What turned me off was that the heater was fueled by propane. I didnât want an open flame in the car. However, when a heater was an option in cars, many motorists installed a Stewart-Warner Southwind gasoline heater. My cousin and her husband had this gasoline heater in their 1949 Chevrolet.
That is the ultimate goal . Until they can go 450 miles on a charge and recharge in 15 minutes or less I am not touching them . And these states forcing this down peoples throat isnt going to help the situation . Just taking more of your freedom away . The rest will shortly follow . No more natural gas furnaces , stoves , gas grills . All your toys will be taken away, 4 wheelers , snowmobiles, boats , rvâs , motorcycles . Cant have home backup generators because what do they run on , natural gas or propane . The laugh of the day came yesterday when I read Bill Gates is going to invest in keeping cows from burping . Are you serious , I am sorry but cow burps and farts is not going to destroy this earth .
Do you mean there are no resistive heating elements in the heat pump or that there is not a separate backup system?
No separate backup system. Strictly the heat pump.
Is heat exchange with outside air or the ground? Ground temperature is well above freezing a few feet beneath the surface. If I built a new house now I would consider a buried heat exchange system.
Outside Air. If I was building a new home, Iâd definitely look into it. But not about to rip out my furnace and AC units to add two heat pumps.
Agreed. I have two perfectly good HVAC units and Iâm not changing them. The main one is a natural gas FWA furnace with a new AC unit for the 1st floor and basement and the other is a 3 yr old heat pump for the top floor. The NG water heater is 25 hrs old and may need replacement soon. I might consider an electric water heater that heats on demand. Itâs more expensive initially but doesnât use power to heat a reservoir. Provides unlimited hot water too.
If it is with ground it should be called geothermal. I believe the outside air heat pumps either donât work or become much less productive when the outside air is near freezing.
Heat pumps can work below freezing (but this is for a very well-insulated building):
It doesnât stop working below freezing, but an add-on heat source could be needed.
Here in NH new construction has to meet a certain insulation standard.
EVâs are good for some things, not so good for others. Vehicle lifespan is another factor to consider. Not that unusual to see 30 year old gasoline-engine cars still on the road. Have to wonder if 30 years in the future what % of todayâs EVâs will still be on the road?
What makes you think they wouldnât? Probably have to service the batteries at some point. But the electric motors have the potential to last 40+ years. Most other parts of EVâs and ice vehicles share the same components.
If you own an EV and you decide to REPLACE the whole battery pack instead of getting it serviced then you have no business buying an EV in the first place. There are many places around the country that will determine what cell(s) in battery pack are bad and just replace them.
And when manufacturers started making vehicles with Fuel injection - most mechanics didnât know how to work on them. Same with Electronic ignition. Or Direct injection. Or Hybrids. Good mechanics will learn. As EVâs become more and more common - GOOD mechanics will change and adapt. The bad ones will die. Automotive training facilities already offer classes on how to service EVâs. The manufacturers offer training for their technicians on EVâs.
Same can be said for ANY ICE vehicle.
Well fine for around town with home or work charging, but not for long range driving where you need a car to fulfill multiple needs. Then of course there are other issues not being fully discussed or declared.
