One of the advantages of the internal combustion engine (ICE) vehicle is that it is typically 85% inefficient, so it has lots of waste heat that can be used to heat the passenger compartment. With a 90-95% efficient electric motor, this is not the case. There are two methods of providing heat. One can replace the heater core with a ceramic heater element similar to that used in room heater. These provide about 1500 watts of heat; the same as a hair dryer. This type is better for defrosting than heating. There is so much glass and metal in the passenger compartment, that this unit becomes ineffective below 40F. A second method is a water heater (4000 watts) that feeds the heater core. This provides more heat and does not require the removal of the existing heater core; however, it does require more space.
EVA does not have an air conditioning system at this time. One advantage of an EV is that it eliminates two major sources of heat into the passenger compartment. One major source is the 85 percent inefficient ICE; the second major source of heat is the high temperature catalytic converter under the floor board.