Kang's Thoughts

Winter has arrived, and our solar production is seeing a sizeable drop in production. Although the month of November is still incomplete, here is our current solar production history so far:

We were operating at 50% utilization when on of our SolarEdge inverters went down in June, and as pointed out earlier, November is only about 75% completed as of the time of the writing of this post.

Even with the above discrepancies in mind, we can see a gradual reduction in generation from the summer months. From a peak of over 2500 kWh in July to just around 1230 kWh in the month of October. That is half of our peak from July. Based on the November trend, we will have even less.

These reductions got me curious to the length of day variation through the year, and I found this handy chart:

The above chart is customized by our home location of course. From trough to peak, there is a difference of about a 6.5 hours! I must say, I knew there is a difference between the longest and shortest days, but seeing number was a bit of a shock. These short days are made worst by lowest sun elevation on our Southern horizon during the winter months.

It will be interesting to see how much power we end up generating during December which will be our lowest generating month, per the above chart.

The past few days we have met our first signs of Canadian winter. Although winter has not officially arrived, we have received at least a couple of snow dustings that resulted in enough accumulation on the roof to cover the solar panels.

I wanted to record our observation with this “new” experience in terms of the impact to power generation. Below is a chart on solar power generation in the past few days with different weather conditions during the shorter days of our Canadian autumn.

Our highest recorded power per day is around ~110 kWh during a nice sunny, long, summer day in June. We are now facing shorter days with the panels active from around 8am to a little after 3pm, as the chart below shows.

Below you will see what my roof looks like today on November the 18th. Click the video below to see the entire roof.

You can see that we have some panels that are fully exposed, and some that are partially covered. The solar optimizers are optimizing away during these times, and when the sun comes out, we can still sometimes generate above 3500W of instantaneous solar power.

During these dark and short days, we are now definitely eating into our stored electrical credits from Alectra Utilities.

Since our solar installation, and our live commissioning of our net metering with Alectra Utilities, our last payment to Alectra was in May, 2022. Since then, we have not paid a dime to Alectra, but instead we are sitting on a nice credit as the attached snapshot of our bill showed:

As the above bill indicates, we created 372 kWh during the 30 days of this last bill that we received. I was also surprised by the fact that during the summer months, we were still able to generate excess while running our AC without compromising our comfort requirements. The extended summer days and the higher angle of sun’s elevation were very conducive to solar production.

I also noticed our natural gas prices increased by 110% from the same time last year. Below is directly from the Ontario Energy Board (OEB):

Our goal now is to try to switch our heating source from natural gas to electric, so that we can use our excess electricity for this winter’s heating needs. This makes total sense, since our electricity is almost free, while natural gas is not!

There are reports out there saying the rate increase is significantly less. This is because they are comparing against the July, 2022 rates and not the October, 2021 rates, so read carefully.

I went on Amazon and purchased three of these electric based heaters.

At time of purchase, they were $219 CAD each. We tried the cheaper ones, but their fans were simply too loud. These ones are nice and quiet with a very user friendly interface.

The master plan is to set the house thermostat to 18ºC, so that it acts as a backup heating source. While these electric panels will try to heat the house during most of the winter days. We will see how this plan goes. I would consider this to be a win if we can reduce our natural gas consumption this winter by more than 50%, which will effectively normalize the rate increase. In the end, these electric heaters may not be enough. Time will tell.

I also investigated the possibility of installing a centralized heat pump, but current technology is limited to -20ºC outside temperature. I decided to table this for now until the technology matures a bit more. I want a solution that can transfer heat from -30ºC outside to indoors.

Our next plan is to research our water heating needs and to see if there are any electric based tankless solutions out there.

Wish us luck and I’ll keep everyone updated!

Update: November 14, 2022

Previously I got the rates from the Enbridge web site. Below is an actual excerpt from my Enbridge bills. However you compare, the increase is significant.

Update: November 26, 2022

Found this CTV article.