I have avoided getting into this discussion on heat pumps because I started the discussion with my question about the size of a resistance heating element for a small car like the VW and the question was answered. However, everyone is praising the efficiency of a heat pump. Efficiency is not he whole story when it comes to heating a house and maybe a car. A heat pump outputs a register temperature of approximately 90 F. This low a temperature blowing across your skin is not comfortable to a lot a people. A coal fired heating unit register output is over 140 F. An oil fired unit is approximately 140 F and a gas fired unit is approximately 120 F. In addition, a heat pump unit must run a longer time to maintain the heat losses from a house. Heat pumps run most of the time blowing cool air. Fossil fuels output a high temperature at the register and do not run as long. In determining the best method of heating a structure, efficiency must be balanced with comfort.
________________________________ From: EV <ev-boun...@lists.evdl.org> on behalf of Robert Bruninga via EV <firstname.lastname@example.org> Sent: Wednesday, November 29, 2017 9:16 AM To: Electric Vehicle Discussion List Cc: Robert Bruninga Subject: Re: [EVDL] Heat pump vs resistive Heater (never buy another AC unit) For the home, never repair or replace or buy another Air Conditioner! Spend a $100 more and get the two-way Heatpump model. Whether it is a window unit, portable 2-hose unit or whole house AC, replace it with a heatpump. Even if you have oil or gas heat. Run the Heatpump all the time in the winter will save you HALF of the cost of oil for every BTU it puts in the house. At current Gas prices, it is kind of wash, but the advantage of the heatpump is that it can be 100% fossil fuel free when powered by solar or utility subscribed wind. I even hang some old window AC-only units in some rooms or basement joists backwards so they can be used as a heat source in the winter. Just sayin... Bob, Wb4APR -----Original Message----- From: EV [mailto:ev-boun...@lists.evdl.org] On Behalf Of EVDL Administrator via EV Sent: Wednesday, November 29, 2017 10:35 AM To: Electric Vehicle Discussion List Cc: EVDL Administrator Subject: Re: [EVDL] Heat pump vs resistive Heater (OT, but somewhat EV related) On 29 Nov 2017 at 15:07, Peri Hartman via EV wrote: > if you choose a heat pump, make sure it will generate the BTUs you > need at your coldest temperature or supplement it with some resistance > heating. Every home-HVAC heat pump I've ever seen has had supplemental and/or "emergency" heat. They all had resistive electric supplemental heat. I've read more recently about HVAC systems that use fuel gas heat as the supplement. I'd assume (and we all know what that is!) that all production EV heat pumps would also include resistive heating. Very few people will tolerate Yugo- class heating in their vehicles. (The infamous Yugo GV ICEV came with a pitiful heater. Owners who complained were told to keep the blower on LOW position so the air coming out of the vents would feel a little warmer.) IMO fitting a heat pump to a conversion EV is going to be a pretty significant challenge. That holds whether you're trying to make a HP from an existing aircon that came with the ICEV you're converting, or trying to convince a HP system from a production EV that it should work in a vehicle with none of the Canbus signals it expects. I would have no idea where to start. David Roden - Akron, Ohio, USA EVDL Administrator = = = = = = = = = = = = = = = = = = = = = = = = = = = = = EVDL Information: http://www.evdl.org/help/ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Note: mail sent to "evpost" and "etpost" addresses will not reach me. To send a private message, please obtain my email address from the webpage http://www.evdl.org/help/ . = = = = = = = = = = = = = = = = = = = = = = = = = = = = = _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20171129/7fd7780d/attachment.html> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)