The principle is straight forward. When the
sun is shining, water is pumped through the solar collector and is heated by solar energy. This heated water
then flows through a heat exchanger, warming the water stored in the
hot water cylinder. The hot water in the
cylinder can then be used for washing and bathing as required, with your boiler
providing backup heating.
In the summer the water in the cylinder can
reach a temperature of 80 deg C within half a day, and the insulation on the
cylinder will keep the water warm for the next day. Typically the solar hot
water system will reduce your domestic hot water bill by 50%.
The Low Flow System
A characteristic feature of the ISL solar
system is the low flow rate through the solar panel. Most systems in the UK use
a full flow system, based on central heating technology. The advantages of
low-flow rate are:
i. Water passing through the solar panel will get heated up
by about 30 deg C on a sunny day compared to about 3 deg C in a traditional solar system.
ii. The pump is only 3 watts instead of the 50 watts used
on a full flow system making it ideal for powering with a small PV module.
What You Will Need
The systems sold by Imagination Solar Limited have four main components:
1. A 2.7m2 solar collector panel (or more if required).
2. A pre-assembled unit comprising of a pump, control unit and small drain back bottle.
3. A hot water cylinder with solar heat exchanger.
4. A PV module, or mains, power supply.
These components are plumbed together using insulated microbore copper pipe, before filling the solar system with normal tap water. The solar hot water system is normally set up in conjunction with the existing boiler.
There are no running costs for electricity with a PV powered solar system!
Due to the innovative drain back design of the system, no anti freeze is required and there are no maintenance problems due to pressure loss, as can occur in pressurised solar systems.