Probably an old topic, but one where technology is moving at a rapid pace, so perhaps worth asking again. I feel that it should make sense to have solar panels. I’ve had various people around including EDF. Some offered government rebates but were twice the price of others. Others switch sold to heat exchangers. Some clearly came from the school of double glazing salesmen.
We have underfloor heating. Good but expensive. A wood burner is being installed next week. Small house of 100m2. We do not have electric cars, only hybrid.
So, it seems that during the winter you can only hope to draw free power during daylight hours. So then you have to choose when to run washing machines etc. Some say you can use excess power that you supplied to the grid. Others say, get a battery. And others say you need a massive battery or you’ll exhaust it in an hour. Two neighbours who installed panels are not getting what they hoped for.
I am confused. Has anyone here found a good system that really works?
My son looked into this the other year and decided that the investment in a house they hope to move from in the next few years was not worth the loan repayments as they would not reap the benefit. The government rebates did not even feature and EDF did not want to know about it and the bank was the only alternative to financing it but with a brand new car and mortgage payments already insitu, the bank advised them not to tie themselves up further and risk losing it all if they could not work.
To answer part of your question, we have solar panels from EdF. They offered us a loan at a good interest rate but said we couldn’t have a battery because they weren’t good enough a few years ago. This could be more to do with having power going back into the grid, but we decided to take the loan and deal with battery issues once the loan was paid off.
We’ve had solar panels now for about 2 years. We did get a government “bonus” of 1650€ after 12 months. We have a 4.5kW installation and we sell back electricty that is not being used. Our electricty usage from EDF has decreased (I don’t have the figures to hand). We also, every 12 months get a payment from EDF for the electricty that we have put back into the grid. We do not have any batteries - we found them to be too expensive. We calculated with the installation company that our payback period was going to be about 7 years and I think we’re going to make that - it of course does depend on the weather. We also had our quotes checked by France Services - the Gard department has experts who can advise you - maybe the same in other departments.
We have 4.1 kW of solar. The very first thing you need to know is where can you put the panels, and how close to south facing will they be. The closer to south, the more power you will get. The angle of the panels makes a difference as well. There are resources online where you can put in these details and find out how efficient your panels will be. The other thing to realise is that if you put in say 4 kW of solar, you won’t actually get 4 kW. You may get close under ideal conditions at the right time of year for a short while but generally not. Our panels are about 25 degrees east of south and peak at around 3.5 kW. You wouldn’t believe how many installations I’ve seen where panels are facing directly east or west and whoever persuaded these people to install the panels are ripping people off.
We have a power diverter that takes excess power and uses it to heat our hot water. Because of this, we get essentially free hot water 9 months of the year and only usually need to heat the water a handful of times during the other 3 months. There are only two of us though. The rest goes to the grid and we get paid for that. We have a very efficient modern house that is electric only which helps us a lot, and just over 50% of our total electricity consumption comes from solar. The amount we sell gives us back around € 220 per year as well.
As far as a battery is concerned, I looked at this in some detail and it just isn’t worth the cost. The payback period I calculated a few years ago was about 30 years.
Sadly sales people don’t really care what they are selling and seldom understand what they are selling. If they are a commissioned Salesforce rather than saleried they will simply push the part of the equation that nets them the most.
If you can find a local company that has the data for their own installations and are willing to share that information you will be far better placed to see actual solar generation figures. A good friend in the UK did this and the payback was about 5.5 years instead of the 7.5. they were early adopters and got a feed in tariff of £0.57p (index linked) they have earned over £85,000 since install from the data collected from the smart monitor. Like a lot of things, the system works if properly installed.
If you have plenty of land facing south an economic option is to go for self installed panels
allowed up to 3kw simple declararion on enedis website
just plug in
takes a bit of fitting work but not that technical
does seem to make a meaningful change during spring/aummer/ autumn
does require some behaviour change ie run the washer and dishwasher when the sun shines
Have not yet gone for batteries as i suspect prices may start dropping as more EVs come to end of life and i want a system that easily interacts with my Linky meter
The problem isn’t necessarily the battery price. It’s how much you save vs just selling it to the grid, even though we only get 10c per kWh. I used a year of our consumption and production data for a year (every 15 minutes) and calculated when the battery would have charged/discharged when we had a surplus/deficit and how much less we would have taken from the grid because of it. It really isn’t that much.
It was 10c per kWh to sell about 5 years ago, and you get a fixed price when you start to sell which never changes. It won’t have increased I would have thought since then.
If there is a power cut, the solar cuts as well to avoid electrocuting any engineer who may be working to fix any issue. I think it’s possible to engineer an alternative where the solar does continue but you may or may not be able to get that approved. @Badger may know more.
Hiya…similar @Jennifer11 & @ykm71, we had our installed by EDF and sell back the surplus each year. Today…sun is shining and the max output is 5kw/hr and so as another do, we use what we can and the rest is sold.
Can’t remember the costs, but I do recall that at the time EDF financed it at a lower interest rate to savings rates so a no brainer to take advantage and the folk who came and did the installation were extremely proficient on the basis that I don’t less around with electricity.
Hi. I led a small research project on solar panels a few years back. We tested and measured the operational efficiency of some prototype panels that incorporated solar thermal behind the PV in order to reduce the peak temperature in the PV and increase the overall output. It worked, so I would recommend PV with solar thermal combined.
One issue that arose was that the connectors to the panels decay over time, so ideally PV panels would come with multiple blanked off connectors so that you can ensure a much longer life. If you cannot do that I would then recommend more smaller panels, cheaper to replace, rather than larger ones.
I am tempted by low height vertical PV panels, so that we can mount them on our flat garage roof, so they will not then be entirely covered in snow as I observe for neighbours here in the Jura, but stand up robustly to increasingly strong winds with climate change.
When we had our house rewired initially I insisted on surface ducts, so we could eventually run 12v cabling. More and more devices are 12v. The inverters for PV from DC to AC form one of the biggest expenses. This can be avoided if you are not pre-occupied with selling back to the grid. If you look at the fora for living Off-Grid there is regular advice about how people have installed self sufficient systems.
We committed to a long rental electric car for running around locally, but in the knowledge that eg Renault were about to enable their range (as do Tesla and others) to act as house batteries. cf Mobilize Power - Recharge bidirectionnelle pour véhicule électrique Renault so in a years time our next electric car rental will be a Renault. Unhappily their technology does require an inverter.