Category: solar

Sooo… One of my non-game ambitions is to run a renewable energy company. It’s my alternate plan if the game industry implodes or I fall out of love with it (unlikely for the foreseeable future). Anyway… I made one tiny step in that direction today by buying this:

Eat your heart out Brad Wardell!

Ok. Not all of it. I admit that. But I now officially own a tiny chunk of it. It’s the largest solar co-operative in the UK, near swindon. 30 acres of solar panels. Insert joke about it never being sunny in the UK here. If you have read my blog for ages, you will know I have some solar panels in my garden. I can see them from my desk! yay! The trouble is, that small scale solar isn’t as efficient as large scale due to the problems of occasional local shading, the economies of scale for inverters, and of course bulk buying discounts. I bet you get a decent discount on 30 acres of PV panels :D  (TBH, wind energy makes a lot more economic sense in the UK, but people like Donald Trump have some emotional hatred of wind energy that they funnel into campaigning against it, making the planning process for it more trouble than it’s worth. *sigh*)

Anyway, I feel very happy about it. I am going to GDC for the first time next year. I try to avoid flying when I can, because I’m a right eco-obsessive. I’ve never gone to a non-uk games event before, and I’m very skeptical that paying the odd twenty pounds to an ‘offset’ scheme really negates the environmental damage of long haul plane travel. My own tiny 10 panel array in the garden doesn’t even cover my own electricity needs, so I’m definitely in net deficit in terms of energy consumption. Until today! wootage.

Even forgetting the green-ness, I’m betting it’s a pretty good long term investment. Maintenance costs for the park are virtually zero, the fuel is free, and relatively predictable, and even the most anti-green government is unlikely to change feed-in-tariffs retrospectively. I’d rather do this than hand the money to some pension fund manager so he can invest half of it in landmines and pocket the other half as commission.

So it’s a year to the day since solar power got installed at positech towers. how much power has been generated?

1,331 kwh.

The panels are installed, not on the roof, but in the drive opposite my office, which is cool because I can just about see them from my desk, over the monitors. There has been a lot of talk about feed in tariffs etc, so I might as well do the math myself.

The install cost was £10,608 according to my old blog post

1,331 units at 43p/unit FIT is £572.33. assume 50% export at 3p/unit gives another £20. Also, I saved buying 1,331 units at 12.5p/unit from the power company, saving another £166. This gives total income of about £758

However, the FIT rose to 45p at some point along that, and the 3p/unit is rising too, so it’s a bit more than that. The FIT is locked for 25 years (index-linked) so the rate cuts don’t affect early adoptors.

At installation, the projected income was £1,029 for output of 1,845, so basically it didn’t generate the estimated power. why? Pretty simply, it’s a combination of shading in early mornings and early evenings through most of the off-peak, combined with amazingly poor sun in the last few weeks. June/July should be bumper months for solar, but the cloudy rainy days have been incredibly bad lately.

A combination of some tree pruning which has reduced (fairly recently) the shading, and presumably a more usual summer next year should mean for a much better return. I didn’t really do it for the money, I am a green-energy geek, but it’s good to know it makes some sort of economic sense. Energy prices are likely to recover their stratospheric climb after the current recession, which will also boost the economic case. Output would be much higher if the panels were roof mounted (and the installation cost would have been much lower).

Anyway, given that the energy my office consumes is certainly not 1,331 units a year, I’m pretty sure I could make a grand claim that positech is carbon-neutral, and do so with a straight face. Pity about the way everything else in modern life, travel especially, consumes so much energy. I gave up eating beef 3 years ago partly because of its appalling environmental footprint, so I’m claiming some extra points there too. (I don’t miss it at all, lamb rocks!).

Anyway, that’s enough tree hugging for one blog post. I intend to have a sudden outpouring of GSB related bloggage soon.

Ok, it’s been about a month, so lets look at some solar stats for the last 30 days. ( I have 10 solar panels outside my office window, for those new to the blog. I’m in the SouthWest UK)

Total power generated is 189 units. That’s 189 kwH, which at market prices is £23.62. Bad huh?

But wait a second… I earn 3p per exported unit (50% is assumed) and 43p Feed-in-tariff, regardless of usage, plus of course the 12.5p per unit the power would have cost me if I’d had to buy it. That means that really, each unit generated earns me 57p a unit, meaning I’ve generated £107.73. If we wanted to go mad, I’d claim 12 months of that is £1,292 :D

Obviously summer output is WAY higher than winter, but as a counter to that, we have had a shit 30 days in terms of sunshine (unusually so, the month before install was insanely bright).

Another reason to be cheerful in terms of future output, is that we have a big tree casting serious shade around 4PM. We knew about this, obviously, but didn’t realise the extent to which the late afternoon/early evening sun was going to be so bright here. Given that, we may well lop a few feet off the top (it’s BIG) and hopefully that should boost output a fair bit.

here is a chart showing the aggregated output over the time of day…

And a chart showing how massively it varies each day:

I’m sure I’ll be equally boring and geeky when we have lopped a bit of the tree and had a few days without it. Of course, then the sun will be lower overall…. Bah. comparing data is such a pain.

So the solar guys have finished and gone today. I now am the proud owner of my own little ground-mounted photovoltaic power plant. Check out the remote monitoring gadget for proof it actually works:

 

That gadget is the bluetooth-enabled sunny beam monitor that wireleslly connects to the inverter and lets you monitor output. Cunningly, it has built in solar panels itself, for power :D It also has a usb cable for you to power it, or to dump the historical data to a PC as a csv file.

Here is my ‘what I learned so far’:

Ground mount panels are BIG. They don’t look big on a roof, but stick 10 panels (roughly 2KW) on frames in your garden/driveway and you will be surprised how big they are. This isn’t something you want to do in a small suburban garden. We are lucky in that the drive for our house is unusually big and empty, looking more like a car park than a normal driveway, so we still have lots of room left. They need a lot of space between rows of panels too.

Planning permission for solar with a listed building is HELL. Either pay a company to do get the permission for you, to save yourself the hassle, or start the process a year in advance and prepare for stress. This varies by local council, and if your house isn’t listed, and they go on the roof, AFAIK you dodge needing this permission entirely. Lucky you :D

There will be a lot of extra hardware installed by your electricity meter/fusebox. You get a new (tiny) generation meter (middle top of picture), plus a new fusebox gadget (bottom of picture, with big phat AC cable coming into it from the inverter), and another little black box thing (under the generation meter, stuffed with big cables). Don’t assume it will all fit in a tiny space in a cupboard somewhere. We ran out of room and needed the fusebox gadget attached below. I’ll probably get it boxed in one day to look less industrial.

Prices are dropping big-time. My roughly £10k install was £11k just 9 months ago. If you got a quote for PV a year or two ago, get a new one. The panels are getting much cheaper.

Get panels with bypass-diodes. They are more expensive, but worth it. Mine are Schuco. With Bypass Diodes, shading on 1 panel means 1 panel generates zero. Without them, shading on one panel would mean all ten generate zero. This is a BIG deal. Don’t get them without bypass diodes unless you have a south facing roof in the sahara and no trees for miles. Not all panels are the same.

It’s very very cool to have lots of electrical stuff running and your electricity meter not moving. Especially on the day we hear there is another 16% rise in electricity prices. bwahahahaha. I’ll be contacting my electricity company soon to get a new meter fitted which can handle being supplied to. Sadly mine wasn’t one which spun backwards :(

You get a dedicated generation-meter which you have to manually read and report in order to be paid the feed-in-tariff (43p / unit). Entirely seperate to that is an agreement with the electric co that you get credited as exporting 50% of what you produce (extra 3p per unit). This is great,because I will use everything I produce and export bugger-all, so it’s free money :D. This happens because the electric co can’t be assed to install proper export meters.

Lots of boring generation stats to blog over the next few weeks, I’m sure :D. Already earned £1.50 yay!

Now back to programming stuff that explodes.