alt Hacker NewsI'm on a electricity tariff where the per kWh unit price changes every 30 minutes, you're basically being charged at market rate or thereabouts, the prices for the next 28 hours are announced at 4pm every day.
Generally the prices betwen 4pm-7pm are expensive and the rest of the time it's cheaper - although with current world events things have gotten a little spicy lately.
On really windy days you definitely get to see the benefit where prices drop to zero or even negative, which is great if you have an EV or something to dump lots of power into. Looking at todays prices they're like 1-3p p/kWh!
But that doesn't last, as the wind dies things start to get back to normal.
The key with the tariff though is to just play the averages and generally avoid high power usage during the peak periods. My average for the last 2 years was around 30% cheaper (p/year) than what I would have paid if I was on a normal energy tariff.
It will be interesting to see whether that trend continues, especially with the state the world has suddenly been thrown into.
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That's a great system. Like so many things, success comes down to implementation.
In California, for example, PG&E will charge you the maximum peak demand prices while simultaneously paying other states to take electricity during the solar duck curve.
I'm on a similar tariff in the UK and just had a 10kwh battery installed which is just amazing for shaving off all the load between 4-7pm. Whole system installed was ~6k GBP and I think my payback time is going to be < 5 years which I'm super pleased with.
The key is factories ideally are mobile. Follow the winds. Come online and go offline when the wind blows. Use as much free energy as possible to hit yearly production targets and then take the rest of the year off.
How are the fixed costs in this? Here in Sweden I have seen a strong trend that as the grid has become more variable and connected to the European grid, a larger portion of the bill becomes fixed. For most part of the year, the fixed costs are now greater than costs that scale with consumption.
Transmission and construction, crewing and maintenance of of thermal power plants (under the name of "reserve energy") cost a lot of money, which in turn becomes fixed grid costs. On top of that you got consumption costs during periods of poor weather, which in combination of high fossil fuel costs means that the consumption prices spikes. The cost of energy during optimal weather conditions is in contrast so low that at this point they can basically just be rounded down to zero.
....that being said, when you see stuff like this page and news articles about cheap renewable power etc, there are A LOT of negative reactions to it (even evidenced by the comments on here!) because for most people in the UK they never really see any direct benefit - energy prices seem to keep going up and a lot of people are on contracts with fixed rates that rise often.
I'm not sure what the solution is, I know that the price of electricty is dictated by gas so maybe decoupling that will help - but that probably has complications with balancing the grid.
The tariff I'm on (Octopus Agile) suits me as I WFH, have an EV and it's just me living in the house, I can move my usage outside of hte peak periods quite easily and I built a website to help me find the cheapest charging periods for my car based on the prices for the next day. The other day my average unit rate was like 2p per/kWh and I dumped like 30kWh into my car lol
My friend has a car which can charge only when prices are low. I'm not totally sure how it works though, does the smart meter communicate this to the car?
Why did you choose this plan in place of a fixed price plan?
I wonder if we'll start to see gimmicks in home appliances for taking advantage of variable prices.
Like for EV charging I assume it's a basic requirement, you simply wouldn't buy a car that didn't let you adjust the charging schedule based on cost.
But what about... Freezers? Maybe there are scenarios where your freezer could drop 20° below its usual temp while prices are low, and thereby avoid running the compressor for several hours while prices are high.
What about a tumble dryer button that says "these clothes are fine to stay wet for up to 8 hours, dry them at the cheapest moment during that window"?
TBH I doubt these things would really pay for themselves but as a consumer I'd still be tempted by the "lol, neat" factor.
Also I assume the local-LLM heads are already finding ways to have their agents do useful work while the GPU can churn tokens for almost-free.
Also makes me think of fun Home Assistant workflows. Like, "when energy is expensive, just try to keep the house between 16-26°. When energy approaches free, I want to live at exactly 20°". (I assume heat pumps also have ways to take advantage of this in more roundabout ways).