I have a modest set of solar panels on an entirely ordinary house in suburban London. On average they generate about 3,800kWh per year. We also use about 3,800kWh of electricity each year. Obviously, we can't use all the power produced over summer and we need to buy power in winter. So here's my question: How big a battery would we need in order to be completely self-sufficient? Background …
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Five years ago today, we installed solar panels on our house in London. Solar panels are the ultimate in "boring technology". They sit on the roof and generate electricity whenever the sun shines. That's it. This morning, I took a reading from our generation meter: 19MWh of electricity stolen from the sun and pumped into our home. That's an average of 3,800 kWh every year. But what does…
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To recap, we have 5,040W of solar panels, with a 3.6kW inverter, and a 4.8kWh battery. That's a lot of (expensive) gear! What does it mean in terms of energy savings? Over the last 12 months we have: 4,000 kWh generated by the solar panels. 1,200 kWh purchased from the grid. 1,200 kWh sold to the grid. 1,300 kWh discharged from the battery. (Data taken from various APIs and rounded to make…
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Less than a year ago, in August 2023, we installed a 4.8kWh Solar Battery at a cost of £2,900. Whenever I talk about the upfront capital costs of solar power, people rightly want to know what the payback period is. Well, after less than 10 months, the battery has given us 1MWh. To put that in to context, the average UK household uses about 3MWh per year. So (again, very roughly) over a third …
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Just as the UK was entering the first COVID19 lockdown, we got solar panels installed on our roof. Four years later and our generation meter shows they have produced 15,480kWh of electricity. That's a rather impressive 3,870kWh per year. This is what the average UK household uses in electricity: Our roof is non-optimal. We have an East/West split rather than the more usual South-facing…
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I love my solar panels. But the solar panels don't love the British midwinter. Most of the year, my panels produce more electricity than I can use. But in winter we're lucky if they produce 3kWh per day - and most of the time it is considerably less. So our winter electricity bills must be massive, right? Nope. The normal cost per kWh is 28.5p (including VAT). We're paying less than half that …
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Nuclear power was sold to the world as a safe, clean, and economically viable source of electricity. We were told that it would be "too cheap to meter". Even the most ardent proponent of nuclear power will have to admit that hasn't come to pass. Construction costs for nuclear power stations are dwarfed only by their decommissioning costs. Yes, politics and regulation conspire to increase the…
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I'm a little bit obsessed with building eInk displays. They're pretty cheap second hand. They're low energy, passive displays, with good-enough performance for occasional updates. Here's a new one which shows me what the current cost of my electricity is: Background After installing solar panels, a smart electricity meter, and a solar battery - the next obvious step was a smart energy…
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August is meant to be full of gloriously hot days. An endless parade of sunshine and drinks in the park. This year it seemed mostly grey, miserable, and prone to pissing it down at a moment's notice. We all know that solar panels' efficiency wilts in the heat, but do they get a tan work standing in the English rain? At the beginning of August we installed a 4.8kWh solar battery to supplement…
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Please imagine I have an extreme-YouTube-shocked-face as this post's thumbnail image. We recently got a 4.8kWh solar battery installed. Batteries are still somewhat complex beasties. In order to prevent damage to the internal structure, a BMS (Battery Management System) ensures that each cell in the battery gets a fair share of wear and tear. One side effect of this is that our battery never…
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We recently upgraded our home solar storage to 4.8kWh. The battery has sensors to detect how much solar power we're generating, and how much electricity we're buying from (or selling to) the grid. That means... GRAPHS AND STATISTICS! Our battery was commissioned just after midday. This graph shows: 1630 - it was fully charged. 2000 - the sun had set and the battery started discharging into…
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I have upgradeitis. If something newer and shinier comes out, my stupid monkey-brain compels me to buy it. Seven years ago, we installed a solar battery. It was part of an experimental project which looked at creating a community power-grid, so it came at a subsidised price. As I explained to BBC Click, the 2kWh capacity was reasonable - but I expected the future would bring higher capacity,…
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