Solar panels and battery storage

Hello

I’m starting to plan a new roof, solar panels, battery storage and re-wire of our house and wondering if anyone else here uses this type of power.

Ideal world, the bulk of the power comes from solar energy but wondering if such systems cause noise with Naim products?

It could be that mains electricity might be needed as a top up as we have a relatively large 5 bed semi with Hot Tub in the garden and likely to replace the current gas boiler with electric and electric cars in the future too.

Thanks

You’re going to need one hell of a large roof if you’re thinking that mains electricity only ‘might be needed as a top up’!!

1 Like

Last week i was staying at a rented cottage with panels…….the inverter was very noisy. I would investigate a dedicated external supply for your hifi. I fid read that not many current solar and battery systems “island” the property if connected still to the mains if an outage occurs. In simple terms you cannot just power over to battery…….if the guy fixing the outage is connected “live” to your battery. I think tesla and a few have thought this out.

1 Like

Thanks - yeah - it’s quite a big roof but realise it’s unlikely to get everything we use from the panels

The answer is that is varies from what I have read. Yes the Inverter is noisy by design, and some say it effects SQ, some not. I have 3 year old Solar Panels, but do not get any loss of SQ that I can hear. Saying that, I find there is already a lot of noise pollution during the day anyway, so that may be why I can’t hear it. Typically I tend to listen intently at night, so Panels are off.

You will probably find that in dark wet days that you are hardly generating any electricity, so you will be drawing current from the grid most of the day. Your batteries may not cover more than a days usage, so this is when you start to get wise about getting the most when it is sunny. Use weather maps to determine washing days. Mow lawn and use Immersion for hot water when Sun is out. Watch the clouds and possibly delay putting the kettle on for a few minutes. Don’t put toaster and kettle on at the same time, etc

Here are my figures if it helps (I don’t have batteries though)
4.8 KW panels generate 4,600KWh pa (18 panels)
My annual usage went down from 2,900KWh to 1,800KWh
My gas usage also went down by >25% (If over generating I divert to Immersion and electric fire)

Roughly speaking in UK solar energy ranges from around 0.5 kwh per square meter per day in middle of winter (i.e the equivalent of 0.5 units of electricity per day per square metre if 100% efficient panels) to 5 kwh per day in summer. Local variations of course depending on local climatic conditions and latitude, while the energy actuall collectable by roof mounted panels will also be affected by their angle and orientation. So in winter if space heating is electric, even with heat pump to reduce energy consumption to a quarter of heat output, unless you live in a near passive house you would need a huge area to make any noticeable dent, with large battery capacity to store the short hours of energy from daylight hours through to next day (or absolutely massive batteries to save electricity from many weeks earlier).

This is by no means negating the value of solar panels, just pointing out that it would seem unlikely to achieve anything significant in respect of space heating needs for most homes. (And their cost might be better spent on maximising insulation If that has not already been done.)

1 Like

My understanding is that early inverters tended to be very noisy, but more recent designs have improved. Certainly something to research carefully before you commit though.
Regarding how much of your power you might expect to get from solar, I just thought perhaps you were being a little optimistic! My friend installed a hot tub, which his wife uses a lot and he reckons it has almost doubled his electricity bill (in a 3 bed detached house). Electric heating will be another huge increase in usage, as will an electric car, so my gut feeling is that if you’re aiming to cover anything remotely near all your usage you would probably need to cover your roof, your garden and several neighbors with panels to come anywhere close.

2 Likes

Yeah - the hot tub is certainly NOT cheap to run ….

Even if it is expensive, at least you are offsetting what you can. Plus you can be more wise about when to heat it. There are a lot of winter days with clear Skies when you can generate quite a bit of power

Don’t underestimate the benefits of improved efficiency in your electricity usage, though. It’s apparently fairly common that once people become conscious of trying minimise electricity top-up purchases, they dramatically lower their usage.

How do you know the inverter was noisy? Serious question.

HiFi systems actually run on DC, so ideally, you’d split a section of your system and figure out how to feed DC direct from a battery to the DC side of your system’s power supply, without going through the inverter/rectifier phase. Think of the battery-powered phono-stages and line-stages that are out there in esoteric hifi-land, but scaled up. Some serious electrical engineering required, though. I doubt it’s a domestic-scale challenge for most people.

Whilst AC is better for long distances, I have wondered what it would be like if we instead got DC from our local substations. I suppose it depends on how clean they can generate it, but when you think of all your Mains kit with DC power transformers, it does make you think we need a rethink

As an HMO Landlord I wish my tenant’s would use the washing line I have recently provided. Wet days would be a better use of the tumble dryer. Several have Gaming PCs that use 0.5 kilowatts. The electric oven for a 500gm loaf of bread is a bit wasteful when I make 4 x 700gm loaves………

It tends to mean that each rent review it goes up to keep my bills account in surplus! There is a great need to avoid moaning to them about it.

The next step is electronic Thermostatic Radiator Valves (Danfoss Ally) for their rooms and the kitchen. I use SmartThings for other ventures into the Smart Home. Trying to work out how to write SmartThings SmartApps/Device Handlers. Documentation is woeful.

Phil

It was annoyingly noisy to listen to if it was sunny and the utility room was open…….i am surmising the mains might be as well? Could be wrong……but i certainly could not live with that inverter based on its noise alone?

But only if the DC voltages everything needs are the same, as it becomes costly and electrically noisy to transform, and I have in mind that AC motors are better for some reason, or at least there is a greater choice of types of motor (e.g. induction, synchronous etc).

Many are a lot more powerful than that these days.

We installed 27 panels a few months ago, our power bill was cut in half for the first billing period and we’re expecting it be be reduced further. We decided not to include storage due to the current battery prices, these can easily be added later as prices come down.

1 Like

Did you work out a pay back period, and are there Government subsides.

The long pay back and lack of a subsidy has held me back so far, money diverted to the 252/250 :flushed:

Is that monthly usage or annual?