Spirit Energy

14/10/2026

How does the Powerwall 3 decide when to charge and discharge? 🔋

The Tesla app shows your solar generation, battery state, grid import and export, and household consumption in one place. Behind it, a forecasting model uses your usage history, solar patterns and the weather forecast to optimise when the battery charges and discharges.

There's also an AI assistant built into the app. Ask it in plain language what the system is doing and why, and it explains in real time.

Would you trust an app to run your battery for you? 💬

Follow along for more battery breakdowns like this one.

12/10/2026

Which home battery can actually earn you money? 🔋

A virtual power plant links home batteries together through software, so thousands of them act as one big power resource for the grid. On a cold January evening, the grid operator can call on them all at once instead of firing up a gas peaker plant.

Right now, the Fox Evo and SigenStor can join the Axle Energy VPP scheme. It pays £1 per kWh exported during grid stress events, with a guaranteed £10 a month minimum. You stay in control and can opt out of any event.

The Powerwall 3 has no UK VPP option yet, but Tesla becoming a UK electricity provider is set to change that.

Would you let your battery help the grid if it paid you? 💬

Follow for more on how solar actually works in the UK.

09/10/2026

Your home won’t use the same energy in five years as it does today, and your battery doesn’t have to either 🔋

SigenStor stacks up to six modules, giving up to 52.56 kWh of usable storage per stack. You can mix module sizes and add newer ones later in the same footprint, so you start with what you need now and grow from there 📈

The one choice to make up front is the inverter, which is fixed on day one at anywhere from 3 to 12 kW. Size it for the EV or heat pump you might add, so it still fits when they arrive.

Quick tip: compare usable kWh, not the name on the box. A BAT 10.0 stores 8.76 kWh usable ⚡

What would you add first: an EV, a heat pump or more panels? 💬

The full SigenStor breakdown is on our blog. Link in the comments.

07/10/2026

Got a sunny wall but not the right roof? Wall mounted solar might be worth a look ☀️

With a reasonable wall, scaffolding is often simpler than on a roof install, which helps keep costs down. You'll generate around 29 to 38% less than an equivalent roof mounted system, but in winter wall panels can actually outperform roof panels. The sun sits lower, so it hits a vertical surface at a better angle, right when you need the generation most.

Already have a south facing roof array? An east or west facing wall peaks in the morning or evening, spreading your output more evenly across the day.

Would wall mounted solar work on your home? 💬

Follow for more facts on solar panels!

06/10/2026

☀️ The cheapest solar PV decisions are the ones made at design stage. The expensive ones get made on site.

Architects, specifiers and contractors, this live session is for you.
📅 Wednesday 21 October, 10am, online With Mark Golding, Head of Sales at Spirit Energy

What we'll cover:
- How PV works, and how annual output is estimated
- Choosing panels, inverters, optimisers and mounting for flat, pitched and building-integrated roofs
- The DNO, export limit and planning approvals to build into your programme before work starts
- The installation, integration and maintenance factors that should shape early design
- Recent market shifts, and what they mean for specification

Mark joined Spirit Energy in 2016, started out on quotes and technical proposals, and now leads our sales and estimating team. He knows the kit as a user too: his own home has in-roof PV, a battery and an EV charger 🔋

Register for the session in the comments below 👇

05/10/2026

Has your installer suggested capping your inverter at 3.68kW? It's worth asking why ⚡

Above a certain size, a solar system needs approval from your local Distribution Network Operator (DNO) before it can connect to the grid. Some installers cap the inverter at 3.68kW to avoid that application altogether. It speeds up their install and cuts their admin. That's convenient for them, not for you.

Your system should be designed around the next 25 years, not around the installer's convenience. If the grid can take a larger system, you should be using that capacity. If it can't right now, choose a system that can be upgraded through software later, so you're not locked into a smaller setup for good.

Did your installer talk you through the DNO side of things? 💬

Follow for more on how solar actually works in the UK.

02/10/2026

Two solar panels, nearly identical on paper, but only one difference actually matters once shade hits your roof. ☀️

The AIKO Neostar 3 and LONGi S10 are both 495W, with less than half a percentage point between them on efficiency. The gap that counts is shade handling: both use back contact cells, which means a shaded section can effectively switch itself off rather than taking a third of the whole panel down with it, which is what happens on a standard panel when a chimney or tree casts a line across it.

So if your roof has anything that shades it regularly, that spec matters more than the badge on the panel.

Got a chimney, dormer or tree that shades part of your roof? That's exactly what a proper shade analysis settles before you choose between quotes.

Check out our latest comparison:

The AIKO Neostar 3 and LONGi S10 are both 495W back contact panels. We compare efficiency, heat, shade and warranty to show where each one wins.

30/09/2026

The cheapest time to run your washing machine changes with the seasons☀️

In spring and summer, set your washing machine, dishwasher and tumble dryer to run when your panels are generating most. They use your own solar instead of electricity bought from the grid, and over a year that difference adds up.

In autumn and winter, generation drops, so the cheapest slot moves. If you're on a time-of-use tariff, shift the same appliances to your off-peak window and let them run on cheaper overnight electricity. Either way, it's a timer you set once, not something you have to remember every day.

Which appliance in your house would be easiest to put on a timer?💬

Follow for more solar saving tips.

28/09/2026

Over one year, a Tesla Powerwall 3 covered only 56% of a home's electricity, and still delivered over £1,800 in value. 🔋

The reason is how it was set up. Instead of running for self-consumption, it ran in time-of-use mode: charging overnight when electricity is cheapest, at around 7p a unit, using that cheap power through the day, and exporting any solar surplus at a higher rate.

Maximising self-sufficiency isn't the same as maximising savings. The sweet spot is 60 to 80% grid independence. Push beyond that and you're paying for winter capacity that sits idle for the other nine months.

Is your battery set up for time of use or self-consumption? 💬

Follow for more solar saving tips.

23/09/2026

On a small roof, panel voltage matters as much as efficiency ☀️

Panels wire in a string and their voltages add up. Your inverter needs to reach a minimum startup voltage, the MPPT threshold, before it generates anything. On two or three panels, low-voltage ones can miss it early morning, late evening and on grey winter days.

High-voltage panels clear it even on a small array, so the system starts earlier and keeps going later. Ask your installer what your inverter's startup voltage is before you pick panels.

Would you have thought to ask about startup voltage? Let us know in the comments 💬

Follow for more on how solar actually works in the UK.