Category: solar

2 days ago we took our fourth trip up to the farm to take a look at the site. Its over 400 miles a day of driving to do the round trip, so not something done lightly. Luckily this time we had arranged to be there when it was super-sunny, which is always a nicer way to visit a solar farm. Sun might mean no mud, but it doesn’t change the fact that this is a farm full of grazing sheep. 2 days later and I still have not got all of the sheep crap off my boots. After a while you stop looking where you are treading…

Because we are in the phase of the site build where MOST of the panels are up, and they are being wired, there is not much change to see on a day-to-day process. Most people would struggle to notice if the panels in a farm were wired-in. The wiring is always looped around the metal frame, then bundled into metal channels and cable tied together, so its not like you should expect to see cable trailing on the ground. There is a kind of minimum height to aim for with most of the cabling, which is above the height a sheep can gnaw at.

Here is an image near the end of a row showing the bundled cabling that runs along connecting the panels, and how it goes into the big chunky inverter:

Normal inverters just have one ‘string’ of panels connected to them, but industrial ones have multiple strings. This allows the inverter to do clever voltage balancing so that each cluster of panels is operating as efficiently as possible given that some may be a bit more shaded than others at certain points in the day. When you have just 10 panels on your roof, it tends to be ‘cloudy’ or ‘sunny’ at any point in time, and the inverter will adjust accordingly, but when you have 4 acres of panels, the conditions are going to always vary across even just 300 panels (one inverter) so you need the inverter to be more adaptable.

Not all the panels are connected yet. I insisted on being ‘that guy’ who wanted to plug one in personally!

This was our first visit where we saw panels installed on the right hand side of the overhead line. This makes the farm feel much bigger, and it will feel bigger still once that overhead line is moved and the two sections of panels can be joined. Waiting for confirmation on the grid connection works date and the substation and earthing design has been the biggest headache for me in recent weeks. It does feel impossible to get progress to move at any faster rate. Basically electricity generation connection in the UK has been handed over to private monopolies with no demand that they proceed in a reasonable timeframe. You have no choice but to just accept their quotes and their timescales. Its a huge scandal that nothing is done about it, but then we have a government who actively despises renewable energy, so I doubt anything will change until a new government. Very depressing…

On a happier note, it always makes me feel good to get a sense of perspective in photos like this showing how much renewable energy my little company is building:

I also had some genuinely great news, by co-incidence while I was at the farm. I had got ‘indicative quotes’ from the company building the farm for how much I could get for the power, in what is called a ‘power purchase agreement’ (PPA). You sign these for 1, 2 or 3 years with a fixed price to take all the power you generate. Of course in real physical terms, your power will flow to the nearest demand, which will be local villages and a nearby town in Shropshire, but in market terms, someone will contract to pay me for my power, and that could be anyone.

The interesting thing is that there is a dual market here. There is a simple PPA, where someone wants electricity, and they will buy it anywhere. It could come from nuclear, coal, gas, oil, wind or even from France or Norway. There is a thriving free market for this stuff. Then there is the REGO market. REGO is “Renewable Energy Guarantee of Origin”.

A REGO is a virtual certificate you get if you generate a megawatt-hour of renewable energy. It proves that the power came from a real renewable source. The REGO is basically traded on the free market, and keeps people honest. You cant sell the same REGO to 2 people, so it means if 10 companies each want 1,000 MWH, then they need to do deals with renewable generators who can provide that much power. If demand exceeds supply, the price of REGOs will go up, and vice versa.

For anybody super cynical, be aware, this system is real and works. If a company is bragging that they are 100% powered by renewable energy, they need to buy the REGOs to prove it, and only us renewable energy companies have them to sell. If you are getting your power 100% from a company that only supplies renewable generation, this is how that is enforced, and it really works.

In practice, at my scale, its not two separate things. You find a company who both needs power, and wants it to be renewable, and they give you a price for the bundle of the power + REGOs for everything you generate. In effect, this is a premium on top of the PPA I would get offered if I was a gas or coal-fired power station. Anyway… this is all a long technical explanation to say that I got 2 quotes from big (household name) energy companies and they were both WAY HIGHER than the other quotes I got. I am VERY nervous about the finances of this project, but if those prices stay in the same sort of level until I energize the plant (maybe October?) then, I will make a reasonable profit and it wont be a disaster :D.

My life will be far more chill when I finally get a date for the grid connection, or even just for the overhead line move… Fun fun fun.

In case you didn’t know. I run a small energy company and am building a small solar farm with the money I made from selling video games. Here is the company website: http://www.positechenergy.com

We made another trip to the site yesterday. Its a 350 mile round trip, and part of it was in the rain. This was the first time we visited in bad weather, but to be honest it wasn’t TOO bad. The site is basically the crest of a hill, so drainage is excellent, and it wasn’t too muddy. Despite, this they were still transporting solar panels on pallets using tracked vehicles, because…mud is still a thing.

I bought these solar panels about 8 months ago, in a fit of enthusiasm to push the project forwards. This turned out to be madness, as I then had to store 3,000 of them in a warehouse at huge expense. The panel prices did then rise…but then fell. I think overall, it was a bad decision, but not catastrophic. Despite owning solar panels all this time, I had never seen them until today. Also, 60 tons of solar panels sounds a lot, but does it look a lot in person…?

The answer is YES. It does. Its a lot of boxes, and thats not all of them, a lot of them were already fitted to the frames. Its multiple big articulated lorries full of them. On the plus side, I am no longer getting monthly storage bills. On the negative side, I had to pay £700 to the warehouse to load them on to the truck. This sounded a lot, but it is a lot of panels so… I guess its understandable.

The real excitement for this trip was to see panels actually on frames, to get an idea of what the finished project will look like. Our first impressions were that they were being fitted pretty quickly, and that the frames are really high. No danger of long grass obscuring the bottom of a panel! (A disaster when that happens, as it effectively shadows the whole panel, and indeed the whole string).

I posted that picture to give some idea of scale. Thats not a complete row of panels, we currently have a ‘gap’ awaiting the moving of the HV cable. once that is moved we can fill it in and have longer rows. You can just about see that a few rows are now double paneled, and some they have just done the bottom row. The bottom row is first, then they go back with a sort of frame to stand on so they can access the top row and fit those. There was a team of 4 people working together to mark out the location, attach the fixtures, and then place the panels on the rails. While they do this, fresh panels are delivered to points along each row on pallets ready to be fitted.

At this point, the panels are attached, but there is no wiring. A separate team of people (electricians this time) are connecting the panels together to form strings which eventually get wired to the inverters at the end of some rows.

Thats one of the inverters already mounted. Its a 100kw inverter, so about 25x the power of the kind you have if you get panels on your house. The box to the right is the emergency cut out switch. All that metal stuff underneath is just a bracket to attach a LOT of DC cabling to the inverter, which will run at head height along the length of the panels. In cases where the inverter is connected to panels on another row, there is underground armored cable & ducting to bring all the DC cabling together. Further underground ducts will connect each inverter to the substation using AC cable, but that work has not started yet. The substation design is holding everything up!

A picture to show the scale of each solar table next to a mere human. As someone with a small ground-mount array of 10 panels in his garden, its surprising how high up these are, and how tall they are at the top of the final panel. They are fitted in 2 rows height, in portrait mode (some farms are landscape), and each panel is ‘split’ into two, hence the white line in the middle. They are effectively 2 panels each, and have 2 connectors on the back of each one. Each panel outputs 410 watts

and lastly…

When people repeat stupid oil-company propaganda nonsense about losing farming land to solar panels, I’ll be tempted to reply with this. The grass is still very appealing to the sheep, and plenty of room between and under the panels for them to graze. Frankly on a day like yesterday the sheep probably thought the shelter was awesome. Technically the sheep are supposed to be out of the way during construction, mostly for their safety, but they got in somehow, and it turns out getting them out again isn’t easy. They seem to co-exist with the construction site pretty happily :D.

There will likely be a delay of a few weeks before I go back, unless something exciting happens. There are a lot of panels to attach, and then a LOT of wiring to be done, which is still a manual procedure. There is no clever automation or robotics that can do this yet. Actual humans have to walk to each panel, grab a cable, plug it in, then probably cable tie the cabling nicely out of the way, so it stays there in thunderstorms for 25 years. Maybe one day Teslabots will do this, but not this year.

The real hold up on this project has been the grid connection. First it was planning, then grid connection. I could write a whole epic space opera about how much grief it has been. I HOPE that we are now zeroing in on final agreement as to how everything will work, and thus we can a) start building the earthing mesh and connections for the substation and b) get a date for the DNO to move that overhead cable so we can fill-in the final mounting frames and tables and have everything connected.

The project is still a cause of daily worry and stress, because it involves literally dozens of people talking to each other in email threads that are contradictory, out of synch and confusing. Hopefully things get much better soon.

Meanwhile, a reminder of how important it is that we do projects like this.

A week after the first visit to the solar farm, we decided to head back. Its a LONG drive, but a lot had changed, and the next week looks like bad weather so I thought I’d grab the opportunity to take another look.

There is now a LOT of metal in the field! When you see a completed solar farm, it looks like just rows and rows of glass and plastic panels, but what is mostly hidden from you is the amount of metal support needed to keep it all in place. As I’ve mentioned before, you need to be sure that everything stays firmly in the ground for 25 years minimum, so there are no half measures.

With the frames in place now for most of one of the 3 zones, we get a true feel for how large each of the groups of panels (called ‘tables’) are. They are much bigger than the small array I have in my garden :D. I can just about touch the top of the main support posts if I’m on tip-toes.

Now that the frames are in, you get a much clearer picture of how undulating the land is. This looks like a few long rows of panels, but its actually not the full width. We wont be able to finish any of the rows of panels until the overhead high voltage cable has been buried, because you cant be piling tall metal posts in that close to an 11,000 volt cable. Hopefully we get an actual date for that very soon!

In a perfect world, the field for this farm would be completely flat, so the layout of the panels would be very uniform, with one inverter mounted at the end of each row, and each group of DC cables from the tables running along the top, at head height (so we don’t electrocute any sheep!) and they would plug right into the end-row inverters. Then a single trench would run along all the inverters taking their AC cables underground (armored, with sand laid on top, then topsoil, so totally buried and safe) to the substation.

Because this field is NOT flat, you need to wire the tables in groups that will get the same level of sunshine at all times. because of the hill, at sunset some panels in one region might be getting more sun than others. This means that each row is NOT a single inverter, but varied clumps of panels are wired to each inverter. That means SOME cabling in that gap between the rows you see above. That will be DC cabling, but will also need to be buried safely underground. Its an annoying extra complication.

I was very pleased with the progress in the 7 days between site visits. I’m still very nervous about the timing of getting the substation built. We cannot do this until the earthing is buried, and we cannot bury earthing until the design is complete. We HAVE now paid the connection cost to the grid in full (ouch), but still have neither confirmation that its received, or a set date for the earthing. I’ll have to try chasing that up soon, which I hate doing.

Solar farm building is 45% planning permission, 45% chasing people to do stuff, and 10% paperwork and spreadsheets. It’s a horribly stressful business, and its unusual for it to fall ultimately on an individual who owns a company. I suspect most people making the financial decisions for solar farms are accountants at big multinationals, for whom its not *their money*. I do not recommend this path as easy money or a quiet life!

In 4 days time panels will start to arrive and get fitted, which will make the site look much more finished and like a real solar farm. We already have the inverters (now back to Solis instead of Huawei. Don’t ask) ready to fit. BTW the inverters are BIG. I had in my mind that they MUST be big, but when you see pictures they look like domestic ones, but no. Each pair is on a pallet and the size of a chest freezer.

I’ll probably not be at the site next week, but will go back again after that to view the panels and inverters for myself. I like visiting the site and would go there twice a week if it was local, but 8 hours of driving in a day is a bit much, even if I can do about 80% of that on autopilot in my car. How anybody drives a manual car with gears and without cruise control or autopilot for that long each day is beyond me! (I used to do that in the past, but in my twenties).

BTW, just in case you think I am nuts for doing this, and that I should just relax instead, here is a reminder why I am doing it.

Today we drove 8 hours (4 hours from my house to site, 4 hours back) to visit the solar farm for the first time since we actually started work, and only the second time ever. We visited the morning after we got planning permission, but that was about 9 months ago now, which is crazy but true. At last, stuff is actually happening, and I wanted to see it for myself!

Amusingly, one of the benefits of visiting the site while its being built is there are two signs that say ‘site traffic’ which you can follow. Its REALLY hard to find otherwise. It’s so tricky that even with the postcode you can go the wrong way. Last time we blundered around for ages looking for the right field, but luckily this time we could just follow signs, even the amusingly amateur ‘solar’ sign to make it clear we are at the right field :D.

Apparently the gate just next to this had to be widened to allow some of the bigger trucks to get into the site. We then have all the excitement of our new road! We built this road, and it will be there as a permanent access road to the finished site. Its not exactly a tarmacked motorway, but its actually not too bad.

At the end of this road we have a temporary construction area, where a metal interlinked floor has been laid down (which took a whole day), so that HGVs can drive in, and reverse and get out again without destroying the field or getting stuck in mud. Apparently you can put 100 tons on each section of this stuff.

That green box is actually pretty cool, its a diesel generator plus kitchen plus office space all in a snazzy prefab unit that you can just drop on site as a kind of instant construction site HQ. There were plans on the walls showing the site layout, and the most important pre-construction hardware: a kettle. There are some other shipping containers used for secure storage for stuff like the inverters, when they show up, and are currently packed with sacks and sacks of panel-attachment fixings.

The rest of the site consists of lots and lots of rows of metal posts, and 2 tracked machines that basically repeatedly drop big heavy weights in a controlled way to bash metal posts very VERY firmly into the soil:

These are the main posts that form the chunkiest part of the frames. They are taller than they look in this picture, and pretty thick. There are also connecting pieces that will define the slope that the panels will rest on, then finally the rails that will connect them all together so that panels can be attached to them. At the moment, its just a matter of bashing the posts in. They are aiming to get 90 of them done per day, and we need a lot of them. I was told we have another 6 people joining the team on Monday, and a week later, the panels will be on site being fitted. Its going to move pretty quickly from here on. Also, they are in the middle of building the ‘stock fence’ which will be used to manage sheep so they can graze the other half of the field during construction. There is also a ‘deer fence’ that will form the entire perimeter of the site, and eventually some metal gates and a substation! Also CCTV masts.

Thats me trying to look like I do this all the time. Those two rows of cones define a zone of the field we cannot currently work on, because an 11,000 volt power cable is overhead. You really don’t want the pile-driver top to accidentally touch it! Soon, (but annoyingly we are not sure when), that power line will be buried by the DNO in a trench around the exterior of the site, and re-emerge near the substation. Currently, people are working either to the east of the line, or the west, but ignoring the middle bit until the cable is gone. Its a logistical pain in the ass, but its what we have to do in order to be working now, rather than wait for the DNO. We have waited long enough, so its really time to get building now.

I think these are the connecting frame bits, rather than the posts, but I’m not 100% sure TBH. There is a LOT of metal on the site. There is a surprisingly amount of stuff required to build a solar farm that is not solar panels. The big problem you have is longevity. Sure, you can bang any old metal post in a hole and screw a solar panel to it, but the issue is ensuring that its going to stay solid and upright for 25 years (40 preferred), despite driving rain, baking heat, and the occasional incredibly strong wind. Plus sheep scratching up against them, and god knows what else. Everything is pretty industrial, because it has to be built to last.

So… In terms of how physically big it is… its actually pretty big. I half expected to visit the site and go ‘oh its kinda small really, a bit trivial now I see it’ but no. Its going to be pretty awesome. The site looks impressive when you are there even just as a bunch of cones and posts. When I go back and see all the posts in, and some of the frames, its going to be super awesome. With panels and a substation it will be hilarious.

I suspect everyone who does stuff like this is very nervous with the first project, and obviously almost everyone experiences imposter syndrome to some degree or another. Despite that, today’s site visit went really well. I am very happy with the progress, it was good to meet the site manager in person for the first time and talk to him and other people there. I also forgot that its a REALLY nice spot. On a sunny day, the views from the site are really nice. Most solar farms are places pretty flat and boring, but this one is unusually hilly, and surrounded by other hills. I’m definitely excited to go back and see more!

I’m going to try to get into the habit of more frequent updates to my ongoing solar-farm-project, because stuff is starting to happen now. Here is a brief run-down on whats happened since the last blog post on April 3 2023.

Well we had a meeting about the farm progress on 12th May, and there was a lot to discuss. We finally had the details from the DNO about the earthing requirements for the farm, so our high-voltage engineer could look at that and then design the earthing layout for us.

There was then some bad news about the inverters. We were going to use Solis inverters, but the ones we wanted were no longer available, so the plan was now to switch to Huawei inverters instead. These are Chinese, and some people have views of using kit made my Huawei but I don’t. I really don’t think there is a backdoor in them that will let the Chinese communist party turn off my solar farm, but I do think there are a lot of conspiracy-theorists that probably do :D. This change to different inverters might seem like no big deal, but its actually hellishly complicated…

Changing inverters means you suddenly have a different number of strings, and the way the panels are wired up is suddenly different. You might assume (as I did) that the panels were in nice neat rows, and there was an inverter for each row, or each two rows. No! Apparently thats not how its done, especially on undulating land. Its actually a lot more complex than that, and the positioning of the inverters and which panels get attached to each inverter is hellishly complicated, and done by some complex solar-farm management software.

Anyway, this was generally a good news meeting. Mounting frames were ordered, people booked in to do work.

There was then a LOT of emails back and forth about voltages and another meeting on 26th May. This is where stuff got super involved…

I had assumed that you always connected a solar farm at high voltage, and needed a transformer up to 11kv, at which point the DNO takes over. BUT NO. Suddenly the DNO says they have changed their internal regulations regarding what size inverters they let connect directly to them, and it had gone from 50kw to 200kw. Our inverters are about 110kw, so they were suddenly chill about us effectively giving them nine cables from 9 110kw inverters at low voltage (about 410v I think).

This is a BIG DEAL, because it vastly changes who pays for what, and whats included. Suddenly we arent doing ANY high voltage cabling, or switchgear, and we wont need a transformer at all. This saves a LOT of money in terms of connection offers. Apparently I will get a new connection offer tommorow, and the old one will be cancelled.

In theory this is good, but I wouldnt be surprised to find that the lower connection offer is offset by all the other materials and labor price increases that have happened since we started. Sure, its GOOD news to have a number actually come DOWN instead of up, but I’m not getting too excited by it.

Its hard to convey just how complex a project like this is. The change to the offer would mean that we can move our (much smaller) substation closer to the one for the DNO. That means the site layout can be slightly smaller, which means less fencing (which would be cheaper!). However, it also totally screws up our earthing design, because we now have different stuff, in a different place, at a different voltage… arggghhh. The one bright spot is that apparently moving our substation will not be a planning issue. Thank Christ.

Anyway, the truly exciting news is that a ground survey was done 2 days ago, and the ‘setting out’ engineer will visit the site this week, I think wednesday. Thats the very last step before people show up to build an access road and start building stuff with concrete bases and installing ground mount frames and the security fence. This is all getting very close!

The current plan is for setting out on 31st, then the fencing, then access road. 26th June is pencilled in for the day they start building the ground mount frames. I will nip up there when that happens and take a look at it all, and take a stupid number of photos. Its looking quit likely that we get energised this year, and start generating power, and maybe (gasp) earning revenue this year!