Free solar panel discussion

Cardew

davehills wrote: »

Thought:



What's to stop people connecting up an immersion heater on a timer or even a light activated switch. If the tank is well insulated, it'd heat up during the day and they'd be enough hot water for a bath come the evening.

Without getting too technical it is impossible to 'match' consumption to solar panel generation.

Few people heat their water with an immersion heater(many have gas and/or a combi) or use off-peak.

The problem is you just cannot forecast when you will be getting, say 2kW from the panels(and immersion heater is 3kW), Much of the year you will get low output when cloudy. There is little point putting on a 3kW keater if you are generating 0.5kW.

On your point about the government reducing/stopping FIT payments. That might well happen for future installations, but they are hardly likely to renege on those to whom they have already given guarantees; especially as we, the consumer, pay for the FITs not the Government.

pauldreed

Cardew wrote: »

Without getting too technical it is impossible to 'match' consumption to solar panel generation...

Surely there must be gizmo out there that can switch on the immersion heater automatically if, say the panels generate sufficient output, and off again when they don't?
We have energy 'monitors' which can detect with reasonable accuracy how much power is being generated, and we have gadgets which can switch on/off power, such as timers and remotes. Has nobody put the two together and created a 'smart' monitor?

Cardew

pauldreed wrote: »

Surely there must be gizmo out there that can switch on the immersion heater automatically if, say the panels generate sufficient output, and off again when they don't?

An immersion heater is 3kW.

Even with large(domestic) solar PV systems their output will rarely reach 3kW - perhaps on a sunny June day at noon.

There are devices that are extremely complex, and hence expensive,(£hundreds or £thousands I understand) that will match consumption to generated output - but they wouldn't be of much use in UK, especially as heating water as it about the only way to 'store' excess power.

Solar PV is particularly well suited to property in a hot sunny climates that use air conditioning - then there is much more value in using the power generated for cooling.

Gizmosmum_2

pauldreed wrote: »

Surely there must be gizmo out there that can switch on the immersion heater automatically if, say the panels generate sufficient output, and off again when they don't?
We have energy 'monitors' which can detect with reasonable accuracy how much power is being generated, and we have gadgets which can switch on/off power, such as timers and remotes. Has nobody put the two together and created a 'smart' monitor?

Weather compensators have been out for years - you'd think there was something along those lines that would work wouldn't you???

FIT is guaranteed for 25 years but anything could potentially happen before installation. Coalition government has indicated that they actually may increase the FIT and allow early adopters to take advantage too. I guess we'll just have to wait til Oct 20th to see what happens in the Spending Review.

John_Pierpoint

There is it is called an EMMA, but it is not (yet?) cost effective.
It has to recognise that the voltage in the house is rising above the voltage in the mains and then turn on a circuit.

Cardew wrote: »

The problem is you just cannot forecast when you will be getting, say 2kW from the panels(and immersion heater is 3kW), Much of the year you will get low output when cloudy. There is little point putting on a 3kW keater if you are generating 0.5kW.

"Kettle" type elements are available in all sorts of sizes and could be fitted to the tank. I used to have a night storage element about 4 ft long with a second short one, intended for day time top when the tank started to run cold. Once the kids left home we did not need the day time boost so fitted an normal long life element when the double one failed.

Pincher

Got a rejection e-mail from ISIS today.
Fully expected, since my roof is eat-west.

You heat hot water using solar thermal.
Using PV to heat water is just silly.

Gizmosmum_2

I just got a rejection this morning too - my bungalow is south south east facing with 55m2 of space for the pv and a 35 degree pitch. Not quite perfect but almost.

They said I didn't have 24m2 of roof space (true I suppose it's 55m2) and I didn't have a south orientation - also true but as I have more than double the space they're looking for the slight disadvantage of south south east orientation is easily overcome by adding a couple of extra panels. If they were really "switched" on they'd fill the roof with panels and rake the cash in from 6kw.

I guess they must be struggling with the volume - at least I got a response and an option to follow up if I thought they were wrong.

John_Pierpoint

Pincher wrote: »

Got a rejection e-mail from ISIS today.
Fully expected, since my roof is eat-west.

You heat hot water using solar thermal.
Using PV to heat water is just silly.

I would have thought that spending all that extra money on thermal solar, when day time electricity is available at 3p a unit, is just silly?

Mind you I'm still not convinced that paying 41.3 pence a unit to avoid using "fossil" electricity is not also "just silly".

Cardew

Pincher wrote: »

You heat hot water using solar thermal.
Using PV to heat water is just silly.

Their idea was to heat water with PV electricity rather than not use it at all.

Unless the people on the ASG type system use the generated electricity it is just exported and they gain nothing - 'use it or lose it'!!

Even for many of those funding their own system the same applies. They get a payment of 3p/kWh for 50% of the generated power regardless of how much they use in the house.

kensington143

I've just received an email saying our property is suitable. They are sending a contract and whgen they receive a signature they will do a survey. Wondering whether to ahead now
:eek: