Note: This is another entry in the 'Solar on a Strata' blog series.
There are a lot of random topics to catch up on in five months.
Electrical contractor Michael Geldreich turned on the power in test mode on June 11, 2015, and Central Park's solar panels have been running in place now for well over a year. As of September 30, 2016, the inverter has reported total production of 26,033 kilowatt-hours of electricity production, about 8% more than the 23,995 kwh that the 'pvwatts' solar calculator predicted for this period. See the chart above to compare the predictions and actual production each month.
You can see what it's doing today on the Fronius website. Click 'Archive' to see previous days, weeks, months. Warning: Fronius is experimenting with a new format so the website may have changed.
The power generated is showing up nicely, both on MyHydro, and the power bills. The total bill for two months ending August 16 was $39.96, compared with $707.46 for the same period in 2014.
One of the concerns I had was whether birds or squirrels would try to build nests under shelter of the panels. There are gaps at the ends of the rows large enough for probably even a gull to get in and build one, and there are squirrels all over downtown. As of mid summer, I saw no indication of any such activity.
The solar panels and inverter just keep working, but there have been two problems to deal with:
1. Internet access. Because of the cost of a dedicated Internet connection ($70+/month when I last checked) both the inverter and the display monitor in the lobby are connected through a WiFi connection offered by a generous resident. It is very little data so doesn't affect his monthly usage appreciably. However, during the summer he had a house guest who changed the WiFi password, which disconnected us. I had to go to the building to reset it in both places, and then return a month later when it switched back.
2. Temperature. The inverter does throw some heat when it's converting 8-10kw of DC to AC. There are several small fans that circulate air out of the inverter box, but it then collects in the rather small electrical room. This spring we had an exhaust duct cut into the electrical room wall to blow air outside, and I screened below the door to allow a bit of cool air in to replace it. I purchased a fan (top left in the photo) to move out the warm air and asked the electricians to connect it with a reverse thermostat (comes on when it's hot, off when it cools) and rheostat. It's only needed in summer, so there's really no way to recycle that warmth into the building.
Just for fun, I tried a 4" computer fan to see if that would move enough air on 3.4 watts of power, but it wasn't quite up to the job. I left a temperature logger ($20 on eBay) in the room during August and it was up to 36 C a couple of times. Not dangerous, but could reduce efficiency of the gear in the room. We need the big fan.
Last year, preparing the business case for the solar kept me quite occupied (as well as being Strata President) so I did not take as much time as I should have to investigate lighting options. It turned out that the 12 High Pressure Sodium (HPS) exterior light fixtures were not nearly as efficient as I thought. So this spring the owners voted to spend about $4,000 to convert the exterior lighting to LEDs. The winning bid installed new 'corn-cob' bulbs in the existing fixtures, simplifying the job, and it was completed in two days in June, instantly cutting the overnight lighting load by about 1,000 watts (1 kw), and saving about 8-15 kwh / day, or about $700 / year.
Too Much Power ?
Warning: This one is for the geeks. When we originally designed the system, I sized it so that the panels would not generate more electricity than the building uses, so that it would be saving $$ by not buying power at the $0.13/kwh rate, rather than selling extra power back to BC Hydro for only $9.99/kwh. Swapping out the lights put this at risk for the summer months, but in the end even with the reductions from the LED lights, there was still a net power usage even in the June - August period. We won't be selling net power to BC Hydro.
There is more on this topic in the big document attached to the 'Solar on a Strata - Join Us' blog entry.
At Central Park's Annual General Meeting in February, I asked for feedback from the 22 owners present, and it was uniformly positive. People like that the building is doing something innovative, there have been no problems, and electricity savings have met the predictions.
One observation is that the type of energy geeks who will read this blog are a lot more concerned about payback and dollars saved than the average owner. They just wanted to do it, in the same way that some people want nicer countertops, a vacation in Mexico, or a donation to refugees. None of these have a 'payback period', but people buy them anyway.
I have not yet tried to calculate exactly how much money the system has saved, and haven't been asked. It's not a straightforward calculation, especially after the exterior lighting upgrade, but I assume it is close to the estimate of $2,100 that I presented to the owners for the first year.
One anecdote: I met a resident in the hallway who said that she liked that every time she had a shower, the water was heated by the sun. This is totally not the case - the hot water is all from the gas boiler - but it illustrated that the feeling doesn't have to connect with hard numbers.
Effect on Building Value
This spring almost any real estate that was up for sale sold, so it's hard to gauge what effect the solar panels had on my sale. I asked several REALTORs(TM) who showed my unit what thoughts prospective purchasers had to the solar panels on the building. I will post those if I get around to collating them.
In June Paul Merrien - the Proline Property Manager - who assisted us with the decision - and I spoke on CFAX radio for about 20 minutes, during an exciting police hunt you can hear about as well. You can listen on SoundCloud here.- our interview starts at 05:20 minutes in. I also talked about Solar PV at a seminar for the Vancouver Island Strata Association on June 26, 2016. Look for the handouts here. And Alevtina Akbulatova, the Net Metering coordinator at BC Hydro, mentioned Central Park in a BCSEA Webinar. Look for 'September 2016' on the BCSEA Webinars page.
Last year I decided that I no longer wished to be a landlord (not that it was an unpleasant experience). I listed my suite and it sold in March, just before the Victoria real estate market went crazy. Of course, I had to step down from Council. The new Strata Council has accepted my offer of overseeing the system as an unpaid volunteer, so I plan to continue monitoring it and dealing with any problems (or opportunities) which arise from it.
I'm also trying to persuade another strata to reduce their electricity usage, but that's another story altogether.
I remain happy to talk to anyone who is interested in following Central Park's lead. My email address is on the 'Solar on a Strata - Join Us?' page. I have spoken with people from about half a dozen stratas this summer. So far they are all at the investigation stage.
As electric vehicles become more reachable (the Chevy Bolt with 380 km range should be available in BC for around $32K) I hope stratas will also try to facilitate EV charging.Converting from gasoline to electric vehicles will directly reduce GreenHouse Gas pollution more than Solar PV in British Columbia, where most of our power is hydroelectric.Central Park's building is extremely well suited for charging stations, but so far no-one has said they are looking for an EV. Many of the residents just walk and bus which is even more sustainable.