At what electricity price overnight charging at home gets more expensive than filling ICE with gas?

You do realize it is the Alberta 10,000+ tonnes carbon tax or the Specified Gas Emitters Regulation (2004)? These solar farms are PPAs or power purchase agreements as a a carbon emission offset, essentially permits for CO2 emissions in oil and gas.

 

I tried to find the USA equivalent:

Close enough?

Bob Wilson

 

In March 2020, just as covid was starting up, we did a road trip to AZ and nearby states. With plugshare I looked at where I would charge and what the cost would be if we took the Kona. I was surprised and alarmed at the lack of free fast chargers, and how much I would have to pay. So we took the Crosstrek (good on gas) because it was actually cheaper. Of course back then gas was really cheap, esp in the US, and when everyone there stopped driving because of covid breaking out. Trip worked out OK, and we were basically chased out at the end of Mar as we crossed the border back into Canada. First time I have never seen a big line-up there...haha.

In BC, the whole 3 years I had the Kona, never had to pay for a charge ever, even at home. At that time, we had a lot of free chargers in BC, incl fast chargers away from home. And at home we had a free L2 just a few blocks from home which I made good use of.

And this past spring, we did a road trip to Manitoba. Same issue, high charging costs away from BC so Crosstrek worked out well.

Things are different now, of course, with gas way up (except Alberta). But next trip, I will again do the calcs before we decide which car to take.

 

What I am trying to say is that there are regulated and deregulated components to your electricity bill.

Regulated - Transmission, distribution and most rate riders (except G)
Deregulated - Retail charge and admin fee
Government loan repayment - Rate rider G (and others to repay the $1.3bn lost on PPAs)

From what I understand, your electricity bill is 100% variable at $0.40/kWh so it's time to go hybrid!

 

Just a wild thought. Will it be cheaper to buy your own gas generator, run it for a few hours to charge your EV? Again there is a capital cost, and it does not really address the pollution issue but then you do not pay all these other charges. (I fully understand there may be many reasons why this is an unworkable idea, but this question entered my mind when I saw the post)

 

Not sure where George lives, but I heard rural. If he lives on a farm, best bet is to put in your own solar system, off grid. Alberta gets a lot of sunshine.

I have that at my cabin, as does everyone else out there. And works wonderfully. Looking forward to charging my Solterra there next summer.

 

Off grid would not be an option as the batteries would not be viable in the winter. Grid-tied solar is possible with net billing in Alberta (3 year payback), but ethically it is by exploiting variable rate customers from the grid.

 

Why would batteries not be viable in winter? Sure they have less power when cold but they still work. You size accordingly to cover your off sun periods. I use flooded lead acid deep cycle batteries. Some go Lithium Ion, but they are big bucks. Should be cheaper in the future.

The big advantage of off grid is cost. At our cabin I can do it myself and order the materials that do the job, at a fraction of the cost to do it at home. There I am not restricted by regulations and BC Hydro that govern who can install them and what materials are approved. At home I looked into it, and the payback would be more than 10 years. Maybe Alberta would be better (no BC Hydro there). That's why you hardly see any residential solar installations around Vancouver, whereas out in the rural areas, they are more common.

BC Hydro does not like home solar installations as that would take away revenue from them. And with the Site C dam expansion coming online soon, they will have a large surplus of hydro power they need to sell. And it is a monopoly govt agency, so you can't argue with them or go anywhere else.

 

About 97% of the solar irradiance is from Mar-Oct and there is about 3% solar for Dec-Jan-Feb. There is a high risk of bricking the batteries without a generator or grid-tie charging.

Generally net metering is more favorable, but there is a special case where net billing can be exploited with a solar rate of $0.285 export and $0.35 import for the summer and switch to $0.08 export and $0.15 import for the winter. The goal is to import as little and export as much as possible to build a gigantic $ reserve for the winter. In the summer, it's best to find as much free charging as possible so you can sell the kWh instead of importing it.

For example, you can have a July 2022 bill of -$552.58 (plus $50 rebate). It's like stealing candy from a baby.


Why do you think they are so many solar farms and the variable electricity prices have skyrocketed?

 

I ran the experiment with our natural gas fueled, 16 kW, emergency generator. It came in at about $0.47 / kWh versus grid power at $0.12 / kWh.

The air-cooled, emergency generator engines are far from efficiency optimized. Worse, there is no recovery of their waste heat. Grid power plants are the way to go.

Bob Wilson

 

No reason to ever brick your batteries if you have a proper system. I don't run mine below 50%, seldom go below 80% actually. In winter with no direct sun (sun is below tree line), lots of clouds (here on the coast), it still generates enough wattage to always keep my batteries full charged. And of course, in winter we don't use the cabin much. Mostly day trips to check things and do a little fishing.

There are several cabin owners in our bay that live there. I talked to one guy that just built a new cabin (large mansion actually) with everything running off electricity about how well his solar system is working in the winter. He does have a generator back-up. He said last winter between Thanksgiving Day (Canada) and Valentines day he used an average of one hour in three days when the generator would come on. It is surprising how efficient these solar panels are. He referred to white cloud and dark clouds. And they seldom get dark clouds.

And like I said, Alberta gets a lot of sunshine, even in winter. Solar panels are actually more efficient in winter than in hot summer sun. And I am not advocating go all off-grid there. Just enough to charge your EVs and maybe reduce some other load from your electrical utility.

 

Yes but the snow effectively blocks production for up to 5 weeks straight (it does not melt or slide off in -25F weather). Even if you do remove the snow, the solar irradance is minimal with the low arc and 1 hour equivalent of usable sun. While lower temps can certainly stop panels from overheating, the voltages are often too low for production to begin! It doesn't matter if it's a string, micro-inverter, or power optimized array.

The point is that if you have solar, it is better free charge your EV and sell energy ($0.285/kWh) back to the grid in the summer. If you charged at home, it would be about $0.35/kWh in the summer. For example, if you charged for at a 50kWh at a free DCFC, you would save $17.50 not charging at home AND sell $14.25 back to the grid (50kWh solar generated and not consumed) for a total $31.75 benefit. Now imagine getting a Ford F-150 Lightning and doing the same with V2H and V2G.

 

Actually snow does slide off. The panels are not sitting flat on your roof. And we get winds in the winter here which blows snow off pretty quickly, esp at the cabin. We do not get a lot of snow here on the coast, just a few times are year, some none. Snow here is either followed by rain and melting or cold weather (below freezing) which includes a strong outflow wind, esp at the lake, which quickly blows off any snow that may collect on your panels. The few times if any that you may get snow here, worst case is you can pull it down with a long handle brush. The guy at the lake never mentioned that to be an issue.

And I know Alberta gets a lot of wind, summer and winter.

As for voltage, doesn't take much to get panels charging. In summer, I have witnessed some pretty thick cloud cover, and was surprised how they kept charging, albeit at a much lower rate.

 

Last year my array was buried under 18 inches of snow (blizzard) and I lost 5 weeks straight of PV production. It would snow intermittently and then melt, and then snow more over those 5 weeks. It won't be an issue if you are near freezing 32F temps, but it's a different story at -25F. There was a long-term study done for clearing snow vs not clearing snow (multiple roof pitches) resulting in an overall 3% energy loss.

It gets tricky with voltage and bypass diodes when it comes to snow coverage. If you had "full cut" (square) PV cells, when the bottom half is shaded the production is 0W. Half-cut PV cells in landscape orientation also suffer significant losses when the bypass diodes activate.

Yesterday a 12.4kW south facing system produced a whopping 1.38kWh.

 

Where do you live?