Yes, you make a good point, for those of us who only have the furnace fan running when the heating burner is firing, there are likely some other good places to spend our money 1st. One exception may be if you needed to service or replace your furnace fan anyway, at which time it might make sense to consider this ECM retrofit option.

The better fit is for people who run their furnace fan more frequently. For example, we have done the retrofit for a customer who runs their furnace fan 24×7 for 7 months of the year. The fan used to consume 342W, and now the low speed ECM motor consumes 74W for a 268W savings.
At 11.67 cents per kWh that translates to $22.52/month or $157 per year (with 7 months of operation).
550/157 = 3.5 years, which is a very good ROI by most standards.

By all means I agree that grid-tied solar is well worth considering as well!!

Thanks a lot for taking time to add your comments.

-Brent

Cheers,

Randy Engman
Kelowna BC

Let’s compare the Nissan LEAF to the Nissan VERSA (almost identical except for power train).

                              LEAF                     VERSA
EPA Combined Eff.        34 kWh/100 miles	   33 MPG (US)
converted to km          21 kWh/100km              7.13 L/100km
CO2 rate                 0.62 kg/kWh               2.3 kg/L
**CO2**                  13 kg/100km               16.4 kg/100km

So I’m showing that EVs in SK may actually save CO2 emissions, even with our coal power. The main differences from your calculation were that I used the more optimistic energy efficiency of the Nissan LEAF EPA rating, but I was fair in comparing it to the EPA rating of a very similar car, the VERSA, which had a combined efficiency of around 7 L/100km vs the 5 L/100km you used.

In addition, with SaskPower’s carbon capture program, we may see SaskPower’s emissions reduced further (the practicality of CCS is another discussion…), while gasoline will continue to output 2.3 kg/L. (Aside: I found an EPA note saying that it is fair to add an extra 25% to this for extraction and processing, bringing the VERSA up to 20.5 kg/100km. I’m not sure if SaskPower includes extraction for their coal?).

I’m sure another calculation could again show something else. Still, I’d like to add my voice to yours in saying that EVs have *huge* potential for cost savings, and in addition, GHG savings, even in Saskatchewan.

Sparing a slight chance of cellulosic ethanol working out, a trifecta of electricity in transportation, electricity for heating and cooling through ground source heat pumps, and generation of electricity from renewable sources, all done together while employing conservation, enables a real possibility for a sustainable energy system, as I see it.

All the best.

I thought about including that info in the original post, but wasn’t sure what to use for a normal gas car.
On average, gasoline produces 2.3 kg CO2 per liter (based on 8.92 kg/US gal from the EPA page: http://www.epa.gov/cleanenergy/energy-resources/refs.html)

So using 5 liter/100km, which is good mileage will produce 11.5 kg/100km
SaskPower claims 0.62 kg/kWh (from SaskPower email – I’m trying to get a web reference for this value), so at 25 kWh/100km I’d be causing 15.5 kg/100km
However, I generate 80% of my electricity from solar, and pay extra for the remaining 20% to be “Greenpower” – so in theory that should be CO2 free.

I realize that everything – including the solar power – does have some CO2 footprint, but I do not know how to calculate the more complex lifetime CO2 number.

It seems if you are using SaskPower’s electric grid, running an EV may cut your “fuel” cost in 1/2, but may actually increase your emissions by 34.7%. We are very interested in coupling solar electric arrays with EV charging stations as this seems to provide financial AND CO2 reduction benefits.

The Wood Mountain install is 15x180W panels with Enphase microinverters. 2.7kW total install. I see that system produced 4,230 kWh from Jan 29, 2011 to Jan 28, 2012, yielding 1566 kWh/kW over the past year.

This relatively high realized yield was obtained even with a tree and power pole providing shading on the system during some of the year.

The Enphase inverters are said to produce 16% more output than standard string tied inverters on average, and can certainly be seen to help when shading exists.