Sunday, September 14, 2014

Electric Air Conditioning Technology Benefits

Japanese industrial manufacturing giant DENSO debuted a new electrically-powered air conditioning compressor in the Ford Focus Electric in 2012.

Mid-September can be toasty in SoCal

During our first summer of owning a 2013 Focus Electric, the benefits of having a variable-load A/C compressor in terms of energy use have become noticeable as I've observed the Focus Electric's user-configurable Climate energy use display. On days like today, when air temperatures on the asphalt here in Los Angeles exceed 110°F, the Climate gauge peaks at over 4 kilowatts of power when I first turn on the cooling in the hot car. But after running for only 5 to 10 minutes, I can maintain a comfortable cabin (at least in the front seats, with the A/C ducts blowing cool air directly on us) by eventually dropping the fan to its lowest speed - where the display indicates that the Climate system is consuming well under 1.0 kW. In the past, A/C compressors were not variable-load. They were on or off, and temperatures were either modulated by duty-cycling the compressor with an electrically-activated clutch, or by mixing engine coolant-heated air.

Just after entering the Focus Electric in 110°F temps, the Climate system works hard to cool the cabin, using nearly 5 kW. But within minutes, the HVAC system can maintain comfortable temps at under 1 kW.

wrote previously that I do NOT use the automatic thermostat in our Focus Electric in hot weather, leaving the temperature set to "LO" to avoid the HVAC system activating its high-wattage heater to regulate the amount of cooling. I've practiced that for this entire summer, and the strategy works, except that sometimes it gets too cold when temps are merely "very warm" (85-90F), and even pointing the vents away from passengers and turning the fan all the way down doesn't moderate the cooling enough. This demonstrates how effective and impressive the DENSO-based A/C is, but how Ford still should have some way to regulate cooling without turning on its 6+ kW heater. When it's 82F outside and muggy, running the A/C at "LO" will make it really cold inside, and turning the A/C switch OFF results in immediately sticky conditions in the cabin.

And as we head into winter, I'm reminded that the Defrost system appears to run both A/C compressor and heater to clear the windows. This is a typical strategy of all cars, but because the Focus Electric's cabin heater is electrically-powered, and uses a devastating amount of power (while heat in traditional cars is scavenged from the engine cooling system), a driver has no choice but to run the range-sapping defroster in order to maintain fog-free window interiors for safety.

So bravo to DENSO for what appears to be a superb solution for efficiently compressing refrigerant with electricity. I've been able to maintain the same 245 Watt-hours/mile consumption rate that I'd averaged in the winter and spring months before hot weather arrived. I've read that electric A/C compressors are a trend among all motor vehicles, and I'm encouraged by our own experiences.

Tuesday, September 9, 2014

Test Drive an EV Next Week!

September 15-21 is National Drive Electric Week, organized in part by Plug-in America, The Sierra Club, and the Electric Auto Association, and partially sponsored by Nissan.

Events will take place around the U.S. - this search engine promises to locate NDEW events by zip code.

If you live in Southern California, the City of Santa Monica will host the 9th Annual AltCar Expo, where many manufacturers of alternatively fueled (electric, natural gas, hydrogen, etc.) vehicles provide free test-drives to attendees. We attended this event in 2012 and 2013, driving most of the available (and not-so-available, like the exotic, rare and lease-only Honda Clarity hydrogen fuel-cell car) electric, plug-in electric, compressed natural gas (CNG) and fuel-cell vehicles before deciding to lease a Ford Focus Electric last October.

Tuesday, September 2, 2014

Blink Network Introduces Kilowatt-Hour Pricing & Reduced Time-Based Increments

Today, I got an email from CarCharging, the new owner of Blink Network, announcing a change in pricing structure on September 2, 2014 for charging electric vehicles. In "states where such pricing models are permitted" (CA, CO, FL, HA, IL, MD, MN, NY, OR, UT, VA and DC), CarCharging says:
Fees for Level 2 EV charging stations owned by Blink and operated on the Blink Network in the kWh eligible states will range from $0.39 to $0.79 per kWh, depending on the state and individual’s membership status. Fees for DCFC chargers owned by Blink and operated on the Blink Network in the eligible states will range from $0.49 to $0.69 per kWh, depending on the state and individual’s membership status.
Blink's previous pricing schemes sometimes charged the user for hours connected, even after charging had completed. This was a useful strategy to discourage the use of EVSE stations as private parking for EV owner, and to encourage turnover so that more EV owners could have access.

While we have grumbled a few times about paying far more than the a fair price for charging because our parking stay continued hours after charging completed, I think I'd actually rather have the old system that provided a likelier opportunity for any arriving EV owner to take on charge by applying pressure on users to move on after charge completion. I'm really tired of finding EVs (mostly Tesla Model S) using spaces marked "Electric Vehicle Charging ONLY" as private parking spaces, without even the effort of connecting a charging cord. For those of us attempting to make a go of electric-only vehicles, use of public charging is NOT about parking privileges.

10/2/2014 CarCharging's announcement of Blink Network pricing changes