We've had our new solar panels for 6 months. Here's how they've performed over summer. 3,361 kWh Generated 2,445 kWh Exported ===== 916 kWh Consumed Despite working from home every day, using laptops, monitors, microwaving lunch, we only used about 5.5kWh of solar each day. About 72% of our summer generation was sold back to the grid. According to our electricity provider, in those 6…
Continue reading →
Back in 2014, I released a year's worth of solar generation data. I was enormously proud to recently discover that the data were cited in a couple of academic papers: Colantuono, Giuseppe & Kor, Ah-Lian & Pattinson, Colin & Gorse, Christopher PV with multiple storage as function of geolocation (2018) page: 217-232. Elsevier BV. Solar Energy. https://doi.org/10.1016/j.solener.2018.03.020…
Continue reading →
Today is the longest daylight of the year. We had our new solar panels installed just after the vernal equinox - so now seems to be a good time to check in on how they're doing. (Who am I kidding - I look at their output several times per day!) Edent's Solar Panels@Edent_Solar AutomatedToday I generated 24.35kWh of solar electricity. pic.x.com/Mrm4QN8uTy❤️ 0💬 0🔁 020:21 - Sat 20 June 2020 As of …
Continue reading →
We have just installed solar panels on our house in London. We also had panels on our old house in Oxford. How do they compare? Oxford London Latitude 51.753738 51.486880 Panel Size 4000 Watts 5040 Watts Orientation South East/West Split Obviously, it's hard to compare exact weather conditions - lower temperature makes for more efficient generation - but…
Continue reading →
Mostly notes to myself. My solar panels have an open API. But it's only available if I'm on the same network as the Fronius inverter. I can connect my system to https://www.solarweb.com/ so I can access it anywhere in the world - if I have the right password. SolarWeb has an (optional) guest mode. You can view the panels' performance if you know the secret URl. It looks something like this: …
Continue reading →
I have solar panels! The UK mandates that my electricity supplier buys the surplus energy off me. They set a minimum price, known as the SEG (Smart Export Guarantee). My supplier - Bulb - pay me 5.38p for every kWh I export. I pay them about 13p for every kWh I import. You notice the discrepancy? When I tweeted about this, some people got angry on my behalf. How could I stand being ripped off …
Continue reading →
I'm hooking my solar panels up to the Internet! Installation Inverter API & Code My solar panels have an API! It tells me the total amount of power they've generated each day. But there's a small problem... I have panels on the East and West sides of my roof. My solar inverter has two MPPT "String" inputs. That is, East and West supply power separately. Luckily, there's an API for that! …
Continue reading →
I'm hooking my solar panels up to Twitter! Installation Inverter Fronius provide a comprehensive API guide - I wish more companies did this. There are lots of unofficial libraries in a variety of different languages. I've written this code in Python3. This is a general tidy-up of the code I wrote several years ago. Here's how it works.... Every minute, the script runs from crontab. If it…
Continue reading →
Having solar panels on your roof is great - but you need something to turn their wicked DC electricity into pure and godly AC. This bit of kit is called an "inverter". It's a big box which lives in your roof working magic. This is what ours looks like: We chose a Fronius Primo inverter - they're a reliable brand which we used in our previous build. I've been impressed that every few months my…
Continue reading →
A few years ago, we installed solar panels on our roof in Oxford - I've enjoyed blogging about them. I've released open data from them, inspected them with a drone, and measured what happened during a solar eclipse. They've even been on the BBC! But the best thing I did, was release this little Twitter bot. Edent's Solar Panels@Edent_Solar AutomatedToday I generated 17.37kWh of solar…
Continue reading →
Back in 2014, I set up a rather silly Twitter account - @OxfordSolarLive. The premise was simple. A camera took a photo of the sky above my house. It took a reading from my solar panels to see how much electricity they were generating. It superimposed the reading on the photo. Then posted it on Twitter. Solar Realtime Edent@OxfordSolarLive1206 watts. pic.x.com/ip2cp5rrao❤️ 0💬 0🔁 014:11 - Fri 24 …
Continue reading →
(Long and data-filled post ahead!) I've switched to energy provider Bulb (£50 off if you join using that link). They offer a "peak time" electricity charge which looks like this: 23:00 to 07:00 = £0.0815/kWh 07:00 to 16:00 = £0.1235/kWh 16:00 to 19:00 = £0.3263/kWh 19:00 to 23:00 = £0.1235/kWh By contrast, the standard tariff is £0.1359 per kWh. That means my electricity is 2.4x more expe…
Continue reading →
