The Powerwall battery here can be persuaded to time shift all our consumption outside Octopus Saving Session times. Full details in Battery Trick section in this post. We did this for the first time during the sessions below. Clearly it … Continue reading Saving Sessions using the battery – first results
Electricity supplier Octopus have a well deserved reputation for innovation, offering a range of distinct tariffs for EV owners, heat pump users, and techie tinkerers. This winter they have introduced the Octoplus rewards scheme and Saving Sessions. Saving Sessions are short periods where if a user can reduce their consumption they will be rewarded with Octopoints. These Octopoints can be converted into credit on the user’s electricity bill and potentially be spent in other ways in future. The idea of Saving Sessions is to reduce peak load on the distribution grid to reduce the need for expensive, CO2 heavy short … Continue reading Octopus Saving Sessions – the good and bad
National Grid returned as promised. Four engineers arrived on Monday morning and set to work replacing the overhead cable to the house, replacing the tails from the overhead cable to the cutout and fitting a new cutout out in place of the old one that had quite possibly been installed when the house was built back in the mid fities. So now everything from the pole to the meter was new and up to current standards. Did it make any difference? Unfortunately not – still losing 30 volts at 50A. Attention has now shifted to the transformer dropping the 11kV … Continue reading Volts still missing…
The Pod Point EV charger has failed a couple of times recently – no charge to the car and a solid red light. Of course it happens during the Octopus Go cheap rate between 00:30 – 04:30 so we are … Continue reading Where have my volts gone?
We’ve been charging our EV in summer from our Solar PV system for the past couple of years – no special EV charge point required but we do have a battery to buffer the cloudy bits. All the details are here:> But is it really worth it? We used to think so – see earlier post but not so sure today. Here are the numbers for the last 12 months. A total of 789kWh from solar charging, this would have cost at Octopus Go overnight rates £76.46……but we could have exported that energy and been paid £32.35 So our saving … Continue reading Solar EV charging – Time for a rethink?
When do you heat hot water with a heat pump? Sounds so simple and it can be – just set a schedule that works for you in the heat pump controller. Perhaps overnight to take advantage of cheap electricity, maybe late afternoon to make sure there’s plenty of hot water for the evening. We started out by heating the water overnight using cheap Octopus Go electricity – works fine – the heat pump is usually not heating overnight anyway so the hot water didn’t affect the heating. Usually only need about 2 kWh of electricity to bring the tank up … Continue reading Seasonal control of heat pump hot water
Time-based control (TBC) charges the Powerwall when electricity is cheap so you can use less peak rate electricity – saving money. Tesla say “Time-Based Control (also referred to as load shifting) helps you maximise savings through smart charging and discharging of your Powerwall” but don’t go into any details as to how it works. TBC improved with a software update last year. Before the update it would sometimes not fully charge the battery overnight in winter – so the battery wasn’t saving us as much as planned. After the update haven’t seen this issue – the battery charges to 100% … Continue reading Is Powerwall Time-based control any good?
As a general rule anything with ‘smart’ in its title is suspect – Smart motorways, Smart Export Guarantee and Smart Meter all are anything but smart. So what about ‘smart’ homes – are they smart or not? Too often smart just means anything with an app – and usually an app that relies on information about you and your household heading off to their servers. Take smart plugs as an example – they let you turn on and off an appliance, perhaps monitor power consumption all from your phone. But what’s actually smart? Convenient for sure but smart is stretching. … Continue reading A smarter ‘Smart’ home with Home Assistant
Our immersion electric water heater used to be smart – it was controlled by a diverter that automatically used excess solar power. Unfortunately the diverter and the battery would not play nice together so the clever solar diverter became a dumb timer. Worse it was a dumb timer that did not integrate with Home Assistant – it was controlled by the SolarEdge app – so no possibility to automate it beyond a timer, no possibility to exploit all the other information brought together in Home Assistant. Controlling an immersion heater is easy – simply turn its power on or off … Continue reading Smarter immersion heater control
The Powerwall was installed at the end of February 2022 so there’s now data from a full year of it working alongside the solar panels and heat pump to analyse. Here we go… Headline stats House total energy consumption 8637 kWh Import from Grid 4770 kWh Total Solar Generation 4405 kWh Export from Solar 531 kWh House power from solar % 45% Solar self consumption % 88% Total Electricity bill (excluding standing charge) inc VAT £732 Average cost per kWh – inc solar/exc solar 8.5p / 15p All data Mar 2022 to Feb 2023 The above figures are close but … Continue reading A year of Powerwall – how did it do?