On May 26, 3:16*pm, Martin Brown
wrote:
On 25/05/2012 19:12, harry wrote:





On May 25, 9:56 am, Martin
wrote:
On 25/05/2012 09:45,www.GymRatZ.co.ukwrote:

(throwing ideas in the air for discussion and dissection)

The problem is one of cost effectiveness and complexity.

There is no point in saving power usage to create vast quantities of
lukewarm water that you don't need in mid-summer if it makes the whole
installation a lot more expensive and prone to failure.

A rough rule of thumb is that summer DHW is less than 10% maybe as low
as 5% of peak winter space heating requirements. We are just too far
north for solar power to be sensible without market distorting FITs.

How so?
My PV panels generate more energy then I use. I need no further fuel
purchases for the next 20 odd years. *There is no maintenance. *It is
a one off expense.

It makes no economic sense at all without the governments incorrectly
computed market distorting FIT payments.

The same kit installed at a sensible and sunny latitude would yield a
lifetime energy payback of 7-10x that of manufacture. At UK latitudes
you will be very lucky to get 4x (assuming here an unproven 25y life).

I think you will find maintenance becomes an issue after 10-15 years.

Why do you think that?
It will have paid for itselfl ong before that anyway.