1,800 days of minute-by-minute solar generation as Open Data

by @edent | # # | 6 comments | Read ~111 times.
Solar panels on a roof.

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…

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Happy Solstice from @edent_solar

by @edent | # | Read ~114 times.
Solar panels on our roof.

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!) Today I generated 24.35kWh of…

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Comparing Solar Panel Generation – East/West split

by @edent | # # | 7 comments
A graph of two solar generators. Both are fairly even.

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…

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Relaunching @edent_solar. Part 5 – Getting data out of Fronius Solarweb

by @edent | # # # | 4 comments
A big grey box with lots of wires coming out of it.

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…

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Some thoughts on selling electricity back to the grid

by @edent | # # | 6 comments | Read ~164 times.
Email from Bulb saying they've set up an export payment.

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…

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Relaunching @edent_solar. Part 4 – Dual String MPPT APIs

by @edent | # # #
Graph showing the difference between east and west panels.

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…

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Relaunching @edent_solar. Part 3 – API & Code

by @edent | # # # # | 2 comments
Solar Graph.

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…

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Relaunching @edent_solar. Part 2 – Inverter

by @edent | # #
A big grey box with lots of wires coming out of it.

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…

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Relaunching @edent_solar. Part 1 – installation

by @edent | # | 2 comments
Roof of our house.

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…

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Sending 1.2 Million Tweets

by @edent | # # | 1 comment | Read ~7,045 times.
A beautiful blue sky with scattered clouds. Text reads 2586 Watts - 68% battery.

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…

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