So yesterday was the big day and we finally switched on our solar farm! The site is not 100% finished, with a lot of tidying up to do, but for the first time ever, the 3,024 solar panels on the site are finally generating power and feeding it into the national grid. Overall, it will provide power for 300 homes, which is pretty good. That might sound a lot if you are reading this in the US, but UK per-household electricity consumption is actually quite low. Yesterday was a big big milestone, but not the total end of the project. We do not have the monitoring logins set up yet (but the power is being logged by the meter), and we do not have the final construction bill, soi I cannot tell you if/how profitable it might be yet. But here are the switch-on day details:
Annoyingly, I live hundreds of miles away from the site, so we have a four hour drive to get there (including a short breakfast/coffee stop where I recharge the EV). Because switch-on was booked in for 9.30AM, that meant a very early start, and then a long drive in darkness and eventual sunrise. That did mean that the project manager was onsite at sunrise and got some really nice pictures:
Because you have to arrange someone from the distribution network operator (DNO) to come and ‘witness’ the site energization, you have a hard deadline, because they are busy and not flexible. My wife had to come back from holiday a day early to make the date. It also meant that this was a HARD deadline, and everything had to be ready. I had assumed we would comfortably meet that, but when we arrived on site there were about 9 vans and a bunch of people still running cables and connecting stuff. This was pretty scary because the DNO will not wait all day, and there is every chance some initial test fails, or something is wrong. There was a lot of pacing up and down. Also the site manager was beyond stressed. Obviously a good time to just take photos :D.
Because everything was being tested, it was a good time to poke around and look at how everything works. The DNO substation was open and being worked on, which is a rare chance to see inside it. We will probably never see inside this box again, as it is owned by the DNO, and is their responsibility, and only they have the key! The insides are basically some big fuses and switching stuff and a transformer. This is where the power gets converted from about 400v to 11,000 volts to go out into the grid. This box is also where the (now underground) cable that connects the farm comes into the site. You can see that a lot of cabling goes down through the floor and then runs underground out to where it eventually goes back up above ground onto power poles away from the site. There is other, much thicker cabling on the LHS that goes to our big green switchgear box.
Here is the big green box I’m talking about with both doors open:
The left hand door goes into the main room that has all the switchgear and is where all of the phat cables from the inverters enter (from under the floor into that concrete trench, yet to be filled in with earth. Thats the bit that has the fire suppression system in it, and the big cooper bars which are live when energized (see previous blog post). The room on the right hand side is basically the meter and CCTV room. Its got the incoming supply meter (to measure how much power we have imported to site overnight to power minor stuff like CCTV etc) and the outgoing meter, which is the one I care about, and is remotely read to work out how much power we are generating. It also has the wifi router for the CCTV and other CCTV related equipment. Here is the meter stuff:
As I recall LHS is the power supply (import) meter, middle bit is CCTV related and RHS is the important export-tracking meter. I guess what most people are interested in, including me, is where is the big button with ACTIVATE SOLAR FARM written on it, with klaxons and so on. The answer to this seemed pretty vague, and thats in part because we connect each of our inverters through to the DNO substation, rather than there being a single cable or a single switch. The closest we get to it seems to be this button, and ironically this isn’t even my finger, its the project manager pointing at it :D
Also you would imagine there is some big ceremonial ‘moment’ when its activated, but I think such things are only really staged for TV. Basically each inverter got switched on, and then the DNO people check that nothing trips or goes wrong, and then they switch everything on, then switch the power TO the site off, just to check that when that happens, the site correctly switches itself off in reaction (just like home inverters do).
In practice this means there is a lot of nervous pacing while DNO people and ‘my’ people switch things on and off and then give the thumbs up to each other, and then eventually they come over and get you to sign a piece of paper, and declare that its all approved and energized. Any disappointment at the lack of champagne and fireworks is just matched by relief that it happened.
What I do NOT have yet is live (or indeed delayed) monitoring of the site. That should be set up at the start of next week, at which point I will exhaustively investigate all the options and data and write long blog posts about it :D. I definitely felt extremely relieved at the point at which everything was declared live, although frankly the site manager seemed even more relieved than me. I thought he might feint/explode. It was also cool that the landowners were taking a break from looking after their 1,200 sheep (OMG) to come witness the final energization of the site.
It feels almost surreal that its connected. There is other stuff to do, but no matter what, I now own (entirely! no financing!) my own solar farm. It has a peak output of 1,243 kwh (output capped at 900kw), will supply 300 houses, and has over three thousand solar panels. It is the ultimate geek toy. My stupid-ass DJI drone failed me (software awfulness for which I blame google 100%) on the day, so no decent drone pics, but it was untidy and a bit cloudy anyway. As a result I may well frame one of the sunrise pictures to sit above my monitor in my office :D.
I hope you enjoyed following this epic saga of many years. Its not 100% over yet, but this is a huge milestone. I celebrated after the 4 hour drive home with a glass of bubbly, and luckily my celebration-purchase (a chunky watch) arrived as I was typing this blog post. I feel much less stressed, but the true smugness of owning a solar farm has not kicked in yet :D.