How it works

Modern solar panels are extremely efficient. The evacuated tubes provide heat on cloudy, cold , windy days. Ideal for the UK! This is how it works...

The principle is very simple. There are three main components to a solar hot water system.

• A solar panel
• A controller and pump
• A hot water cylinder.

Solar hot water panels use the same principle that heats up a greenhouse very quickly on a sunny day; that is the heat radiation passes through the glass but then on reflection can not escape. We use a very efficient system that magnifies this effect.

A pump then circulates cold liquid through the solar panel, where it heats up and is transferred to your hot water cylinder via a large diameter coil.

The pump is electronically controlled by a unit that measures the temperature in both the tank and the panel.

There are two different type of panels on the market - flat plate and evacuated tubes.

We sell evacuated tube panels. These are the most efficient panels available. They are made up of a series of tubes that plug into a manifold. Each tube is a double-skinned vacuum "Pyrex" glass tube that surrounds a copper heat pipe. This works like a hyper-efficient greenhouse many times over. The heat pipe contains a liquid that vapourises on being heated by the sun and quickly raises the temperature to around 150o C. The cold liquid circulated through the manifold is then heated and pumped through the hot water cylinder.

Advantages of evacuated tube panels over flat plate panels are;

• You can heat water on overcast days
• Smaller surface area of panels required to achieve the same heat
• They work better on non-south facing roofs
• They self clean due to the tight radius of the tubes
• They can be installed in small, lightweight components
• They look sleek and modern

When designing your system the size of panel required will depend on the amount of water you use, the size of your tank and the orientation of your roof. A standard 20 tube panel will supply enough hot water for a typical family. We also stock 10 and 30 tube panels.

If your roof faces east or west then we can provide an East/West kit with a controller and panels to achieve the same goal.

Please call to discuss individual requirements.

Typically you will require a twin coil cylinder. One coil circulates hot water from your existing boiler to heat the water.

The second coil is fed from the solar panel. During the summer this means you will hardly need your boiler at all and during the winter the panel will provide some of the heat saving a lot of oil or gas. There is no time during the year when you will not have hot water, just that you will always have a lower fuel bill!

It is also normal to have an immersion heater coil as an electrical back up.

Controllers and Pumps

The controller measures the temperature of the tank and the panel. When the panel is providing hot water and the tank is cold it switches on the pump that then circulates a liquid through the system. The circulation pipe work is filled with antifreeze. There is a pressure vessel in the system to allow for expansion during the heating and cooling process.

DIY Installation

Basic plumbing and electrical skills are required to complete a self-installation. It is a relatively straightforward job that should take no more than a weekend. Click here to look at our DIY page for a step by step guide to installing the panels.