Adding to my solar system

Skintsaver

Hi all, just wondering if it would be worth adding to my system or not. Either a battery or extra panels.

My current system consists of 4x west facing 400w panels and 2x east facing panels. With a solis inverter.

I have a flat roof which could possibly add 4 panels, but I'd be concerned with the extra weight on the roof. Or maybe add a 5kwh battery? This would need a new inverter or complete stand alone.

What do you think adding either or both to my installation. Or is it even worth the extra?

My current Estimated Annual Consumption 2271.0kWh

jimjames

Depends if you're receiving FIT payments or not as that will have a big bearing on income and may negate your existing payments.

Martyn1981

Hi, slight digression, but have you heard of plug and play solar, often referred to as balcony solar?

This becomes 'legal' in the UK on the 27th August. However the full rules and regs will need to be checked, and the DNO notified (I believe) especially if you already have PV.

Just a thought if something like that may be a simple and cheap addition for you, allowing 800W feed to a house socket (maybe 2x 500Wp panels and a 800W micro-inverter).

You also mention a battery, and from there, the next step may be a bi-directional powerstation with PV as plug in. But, the permission on the 27th currently excludes battery systems. I suspect this is just to get the regs and permission through quickly, and that batteries will follow. After all, PV into a micro-inverter, limited to 800W into the home circuit, is no different to the micro inverter being in a power station that in turn is limited to 800W feed back into the house circuit.

If PnP PV and batts become allowed, then you could get a 5kWh power station, with perhaps 2kWp of panels, limited to 800W. These also have AC out sockets which are typically ~2kW.

[Edit - Just a guide, but perhaps ~£500 for 1kWp of PnP solar, or ~£2k for 5kWh battery and 2kWp of solar.]

You may be interested in this thread discussing the Ecoflow Stream product (I have them), and others are available, with Jackery launching their SolarVault 3 any day now in the UK.

EcoFlow Stream "plugin" solar

Martyn1981

https://forums.moneysavingexpert.com/discussion/comment/82103004#Comment_82103004

You can add to a FiT system. But 400Wp panels would suggest to me that the install was post FiT scheme in date.

Screwdriva

Would be useful to know when your system was installed and alongside an image of the roof aspects (to show us how much real estate is unused). I have expanded my system (twice) and highly recommend it but only if it does not void a FIT contract.

If you are on SEG, it's a no brainer.

paul991

I am on a Fit contract and the adding of a battery 3 months ago has stoped all my imports of electric and gas since fitted .Early days yet but should pay for its self in a few years, the Axle scheme being the icing on the cake.

Skintsaver

This is my roof, at the rear I have a flat roof, I wonder even if I could had 4-6 panels on the existing string of 2?

I'm on Seg, system was installed free if charge by a government scheme a few years back, I own it entirely. I think I can alter or extend the system.

I wonder what it would cost to say add 4 panels or a battery. And what cost savings id actually gain.

Newbie_John

But what is your goal? Improve export, decrease consumption?

What tarrif your're on import/export?

Are you at home most of the time? just evenings?

Skintsaver

https://forums.moneysavingexpert.com/discussion/comment/82103474#Comment_82103474

I'm home evenings out nearly all day, my peak is only around 1.1kwh so only really covers half of my appliances usage.

I guess adding another 1kw of panels will get it so when my washing machine and dishwasher kettle ect it'll cover this usages fully, but a battery may be better as it'll cover for the evenings when I'm actually in, and maybe in the future move back to Octopus and buy cheaper electric when the suns not so strong.

Screwdriva

A SEG tariff allows you to expand the system without issue. I recommend reading @JKenH's thread on his system expansion. Then, I would suggest you contact an installer who is willing to:

1. Relocate all the existing panels to the flat roof
2. Install as many as 24 Eurener 515W bifacial panels to fill your East/ West roof aspects
3. Replace the Solis with either a SolarEdge inverter if no battery is required OR a Tesla PW3 if a battery is desired.
4. Apply for the G99 for the much larger system

I can't tell which roof is yours from the image shared but if it is the one on left, you will be able to fit 24+ panels on both aspects of that roof alone. With the proportionate G99 export allowance from your DNO (11KWh) + the right tariff, you will experience a dramatic increase in your export £ earnings.

Reed_Richards

https://forums.moneysavingexpert.com/discussion/comment/82103555#Comment_82103555

Presumably step 4 comes before steps 1, 2 & 3 in case the G99 application is refused?