Thanks for "showing us the numbers," Roland! It really demonstrates the tremendous energy in fossil fuel, and the relative paucity of energy in a battery.
In this part of the world, heating is more the issue. I'm planning to use a diesel water heater (as found in many marine craft) plumbed to the original heater core. It should use under a gallon of fuel over the entire winter. On 2014-08-03, at 07:24, Roland wrote: > Before selecting a A/C unit, a calculation of how much heat gain or lost > there is between a inside surface of a structure and the outside structure. > > One ton of A/C is equal to 12,000 bturs. > 3420 bturs equal 1000 watts. > > The formula is: bturs = SF x u factor x TD > > SF is the square foot area of the exterior surfaces > U is equal to 1/R > TD is the Temperature Difference between the temperature of the outside > surface to the inside surface. > > Calculation for a passenger compartment of a vehicle not insulated: > > Single pane class is 1 R-Factor > Single panel of sheet metal is 1 R-Factor > > Therefore the u-factor is 1/R = 1u. > > For heating loss, we use 100 F. degree temperature difference (TD) to > maintain a interior temperature of 70 F. at 30 below 0. or TD = 100 > > For A/C heat gain, we use a 70 F. degree temperature difference (TD) to > maintain a interior temperature of 70 F. at 140 F ambient or TD = 70 > > The calculation which I use for my EV: > > My SF = 175 SF of the interior passenger > The u-factor would be 1/1 or 1U if not insulated > The TD = 70 F. > > Therefore: > > Btur's = 175 SF x 1 U-factor x 70 F TD = 12250 bturs. > > One ton of A/C = 12000 btur's > > Minimum size of A/C unit will be 12250/12000 = 1.02 ton > > Adding insulation which I install two layers of 1 inch soft foam in the door > panels and firewalls. Insulated the floor with 1 inch of firm DOW blue board > foam with a layer of 1 inch soft foam and carpet. This reduce the btur's to > about half. > > Heating only takes 640 watts at 120 vac 60 hz (continuous ON) at 0 F. If I > want the heater to cycle, than I switch in another 740 watt heater. The > power comes from my rotating inverter/alternator that is rated at 7kw. > > Roland > ----- Original Message ----- > From: Jan Steinman via EV > To: [email protected] ; [email protected] > Sent: Saturday, August 02, 2014 11:22 PM > Subject: Re: [EVDL] Hybrid Mustang: AC or DC? > > > From: Ben Goren via EV <[email protected]> > > > > ... are there heat pump systems rather than compressor units that might be > > more energy efficient? > > The compressor-based system in almost all consumer things that reduce > temperature *is* a heat pump. > > The only one that I know of that is different is the "Einstein evaporator" > used in many multi-powered camping refrigerators. > > :::: Rapid growth in the human energy base has broken down old biological and > cultural diversity, and simultaneously led to proliferation of human numbers > and individual diversity. The climaxing and decline of energy will inevitably > result in a reduction of human numbers, and possibly individual diversity, > while stimulating the re-emergence of localised biological and cultural > diversity. -- David Holmgren > :::: Jan Steinman, EcoReality Co-op :::: > > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > For EV drag racing discussion, please use NEDRA > (http://groups.yahoo.com/group/NEDRA) :::: On a planet with a rapidly changing climate, Canada should be figuring out now how to wind down carbon-intensive resource extraction. Otherwise we may soon find that we're producing masses of stuff we can't sell. But anyone who even hints at this idea in Canada is regarded as nuts. Any politician aspiring to national leadership who says such a thing can kiss his or her political career goodbye. -- Thomas Homer-Dixon :::: Jan Steinman, EcoReality Co-op :::: _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
