As you may have heard, we’re running a pilot to test installation of solar panels and battery storage with Lightsource Labs - I’m Jo, one of the PP team members selected for the first phase of the trial, and here’s a bunch of my early thoughts I thought I’d share with you all. Hope you enjoy the read - ask me any questions if you’d like.
So, we had the panels and battery installed, Tribe (the platform to monitor and optimise energy usage) profile created and were given the app to stare at - but no one warned us it would be such a game changer, turning us into total nerds.
Earlier this year, my husband and I bought a 4-bedroom semi detached house in a quiet corner of the Forest of Dean district, in a village of Sedbury. It’s just the two of us in the house at the moment (will be three by the end of December).
We both work from home full time, no pets, two petrol cars. We’d love to swap at least one of them for an EV - in fact, we’d like to only have one car but that hugely depends on our work patterns and childcare needs in the future. We are a frugal (but sensible) lot, conscious about our outgoings, trying to lead a sustainable lifestyle, minimising food waste, recycling and repurposing. We used to think of ourselves as forward-thinking energy consumers, embracing smart metering, staying on top of the balance of monthly usage vs payments and so on. Then along came Tribe.
The second the installers left, we were immediately glued to the screens of our phones (both of us have Tribe, and we also installed it on our house tablet, to really keep on top of things, right?).
In the first week, we would constantly have the app open, scrutinizing every single spike and dip, trying to map the graph to our appliances and behaviours around electricity usage. There would be a lot of ‘what on Earth has caused this?’ and ‘this is not possible!’ - but also ‘look, we were still generating and it’s raining, something’s wrong!’ or ‘we were sound asleep by then, what is this huge usage spike?’.
Slowly - and with a lot of help (and patience) from Lightsource - we began to understand things better. The huge overnight spikes turned out to be tiny (they just look massive at 7AM, when the display only shows 7 hours of that day, not the whole day) and are caused by the dishwasher finishing a cycle we started at 11PM. The weirdly oscillating, overnight, pattern is the fridge (the way it runs, it only switches on to cool down, then switches off, then back on again). Yes, a rain cloud still generates energy, if it’s bright enough. We also found out that the most energy-hungry device at our home is the electric shower, asking for about 8kW (!) when it’s turned on. Solar and battery combined can’t support this on their own so there’s always this really annoying, red spike of grid import marking the morning shower.
The evening spike you can see above is our dinner. Our electric cooker has 5 hobs and 3 (yes, three) ovens. I’m pretty sure if we switched all of them on at the same time, the demand may just about equal the shower. But that’s not the point.
The point is, we started having completely unexpected thoughts and ideas, because of all that. Like, for example:
Let’s get another array of PV and generate loads more. (Not sure what for exactly, but felt like being more self-sufficient).
Let’s buy another battery. Or two. Store everything up and never have to use the grid again. (Someone didn’t quite consider that there’s winter, as well as summer, but that’s ok, we’re new to the business.)
Let’s check the weather forecast and hold off on doing our washing until it’s sunny. (Someone must have forgotten this is the UK, not Cyprus.)
Let’s not use the downstairs shower (#annoyingspike), just the upstairs one, on a boiler.
And so forth. Surprised we didn’t come up with setting a tent up in the garden and not using any electricity whatsoever.
We’ve been discussing these sorts of ideas at lunchtime and in the evenings quite a lot these days. What if-s. By mid August, we were signed up for SEG with Pure Planet - feeling like we’d missed out a lot in the days prior, with all the wasted exported electricity.
Then came a sudden, sombre realisation, that we won’t make megabucks on all the tons of our exported energy. Firstly, because it’s not gigantic (only looks like it, because we’re consuming very little during sunny hours) and secondly because 5p/kWh is really not megabucks. How could you then make good money on SEG? Adding more PV, yes, but what’s the cost-benefit ratio here, if the price is always 5p/kWh? Also, the export output in domestic properties is limited to 3.68kW which makes you think again if it would really be worth it.
Then you realise what we really need is dynamic pricing, following the demand - so that we could start deciding when to export, to get the most out of it. Ah, wouldn’t that be great? We could discharge our battery at peak times, especially as our own peak usage falls outside the greatest grid demand (we start cooking at 8PM).
But hang on. If we then have no battery left, would it not make sense to import for less outside peak times than at peak demand? Otherwise it’s cheaper for us to use what we generated and stored. Feels rather selfish but without dynamic pricing (so on a flat unit rate 24/7), it’s the default approach. What allows dynamic pricing for suppliers is half-hourly settlements (so that the supplier can pay and pass through real market price, with half-hourly precision) and what enables it is the half-hourly usage profile obtained from a smart meter.
We’re getting there - our supply is already being settled half-hourly, for the benefit of Pure Planet only, for now (so we keep hoarding what we generate, for now). I’m hoping that with half-hourly data collection becoming commonplace, we’ll see the rise of dynamic pricing, for both import and export. That’s when we’ll really become forward-thinking, modern energy consumers.
Now back to staring at Tribe.