Sorry, been away for a while. Here's where I hold up my hand. I am in the solar panel and battery sales business. If you're a large daytime electricity user, possibly greater than 5,000 kWh per year or spending £1,500 or more per year on electricity, including standing charge. Consider just getting an AC attached battery without solar panels, you should get a return on your investment in 7 years or less. There aren't many investments out there where you can get your money back in 7 years. Solar Panels generate lots of electricity during the time you least need it - during the daytime when it is likely you are all at work. Using a battery will capture that excess daytime electricity and store it for you for when you will need it the most, when the sun goes down. With a battery fitted, for 5-8 months a year, depending on how much electricity you use and how much solar generation you have, you'll probably never have to buy expensive daytime electricity again. Charge the battery with cheaper overnight electricity during the low PV generation winter months and it will run your house all day and night. If you have already have solar panels on the roof and no battery, consider getting a battery. If you have an ancient and lucrative generation tariff, keep it, add an AC attached battery, capture all the unused electricity you generate and store it until you need it in the evenings. Keep the Generation tariff. Ditch the Feed in Tariff you have (3-6 pence per kWh for energy exported) and use something like Octopus Flux export tariff (15p per kWh exported). Alternatively get an EV charger fitted together with an AC attached battery and buy lower cost overnight electricity from the grid to fill your battery at 6-7 pence per kWh. Match the battery storage capacity to your average daily usage in kWh. Look at your electricity bill, it will tell you (in kWh) either your daytime electricity usage if you already have an EV charger or it will give you your annual electricity usage in kWh. Divide that number by the period of time that the consumption was measured over and you can get a crude idea of the size of the battery you will need to run your house daily. Don't forget that you'll be moving to an electricity tariff where you can buy cheaper overnight electricity, so take that storage capacity and multiply it by 4/5 as you'll only need the battery to provide electricity to the house from 05:30 am to 23:30 pm every day (Intelligent Octopus Go tariff at 6.75 - 7 p per kWh depending upon your postcode) If you are considering any form of heat pump, and you don't already have wet underfloor heating in the ground floor of the living area, get an AC attached battery, you get a faster return with just a battery and no solar panels. Heat Pumps do use a tremendous amount of electricity, With an appropriate heat pump electricity tariff, you'll get 3 x 2 hours a day of lower cost electricity. Charge the battery during those periods and discharge the battery outside of those hours to run your house and the heat pump. See my note below on what battery you might want to consider for this application given that you can charge and discharge some batteries multiple times per day for 10 years. What should you buy? Well, just like a Ducati, you should always buy a product with easily available and accessible support infrastructure with a good manufacturer warranty. Always check TrustPilot and FaceBook for feedback or user forums on the manufacturer of products being proposed to you, and guage the quality of the support users are receiving from their manufacturer - you'll read horror stories out there about manufacturers no longer trading or being used as a beta test site for software and features disappearing with new software releases. Remember, you could buy a much cheaper Chinese motorcycle which is great until it goes wrong, where's the support infrastructure or spare parts to help you and your investment? With a battery, it needs to have a manufacturer warranty which is either unlimited cycles (charging up and discharging) during the warranty (Tesla does with it's 10 year warranty - I know, I dislike Musk's political leanings too) or at least 5,000 cycles (= 1 charge and discharge per day for 13.7 years). Remember, that cycle count will be embedded within the battery and can be read remotely in case of a warranty claim. Consider either the Tesla Powerwall 3 or the BMW designed battery (Vision) from Solarwatt. The family which owns most of BMW also owns Solarwatt and the BMW Munich HQ is covered with these panels. It has a good cycle count and integrates with their high quality solar panels which feature glass front and rear and are guaranteed to produce 90% of the original panel output at the end of their 30 year warranty. I've got customers where we removed their slightly cheaper Chinese made solar panels after 5 years usage because their PV system was generating less than 50% of the output it was originally measured at after just 5 years. Solar Panels - always choose glass front and rear panels and look at whether they have a guaranteed degradation warranty. All panels will give you a 25-30 year manufacturer warranty but what will they produce during that period? If aesthetics of your roof are important, choose an in-roof panel where the panels replace the tiles and sit in trays which are at the same height as the roof tiles, usually only a 10% premium on surface mounted panels but they look so much nicer (newly built houses tend to do it this way whilst they're built - so it must be good value). Also consider solar tiles especially if you have a nice slate roof. Again these replace the slate tiles and you'll have to look twice to spot them on the roof. Keep an eye on the market for glass driveway based panels which will generate electricity when your cars are off the drive whilst at work. Ground mounted solar panels in a field will need planning permission if you want to install more than about 4-6 panels depending upon their surface area. Wind turbines, as mentioned previously, you'll probably need planning permission and there are limits on how close to a boundary they can be installed. Farmers should definitely consider them as there are asset finance companies out there to help with the capital purchase. Free Solar Panels installed on your roof. Don't do it, if you ever try to sell your house after installation you'll need dispensation from the company which installed them, there are some real horror stories out there about hosue sales falling through because the solicitor couldn't get the permission in time. Green Energy Loans. Your mortgage provider may offer you a 2, 5 or 10 year lower cost loan for solar PV installations as the Bank of England incentivises them to do so. Most of the major High Street Mortgage companies and Banks offer such a vehicle, search their websites for such loans. Most estate agents do not see the value of a solar PV and battery system added to a house, it adds no value to your home in their eyes. So if you invest in solar and batteries be prepared to live there for 10-15 years to get a return on the investment. You can always take an AC attached battery with you to your new home, expect to pay up to £1,000 to get moved and reinstalled. Local council low cost bulk buy solar and battery initiatives. "Buy cheap, buy twice" for the reasons I mentioned earlier - it suits some people, not most in my experience..... DM me if you want some further advice -Steve
