“It seems like a non-stop trip of Europe at the moment which does get me worried by the amount of flying I’m doing, but the alternatives require much more of what seems to be the most precious thing I have at the moment – TIME! I am convinced, however, that every trip is necessary, worthwhile, and will certainly have an overall beneficial effect for us and our planet!

Here at SunGift Solar we are committed to offering our customers the best products available. A key part of this is thoroughly researching and testing these products to ensure that they stand up to manufacturer’s claims. We always try to visit manufacturing plants, company head quarters and meet with the key people involved to see for ourselves what they are all about.

As part of this last commitment last week I went to Valencia to visit Siliken whose PV modules won 2010 Photon Test, producing more kWh per kWp than any of the other 47 manufacturers tested.

This really was an exciting conference covering all energy related issues from electric vehicles to zero carbon cities.

The past few months have seen some huge developments in the field of renewable energy. These developments are almost certainly going to have an impact on the way we all use energy.

Until a few months ago, solar thermal hot water heating had been the most cost effective way for people to generate their own renewable energy - for every pound invested it has usually delivered the highest units of energy.

The controllers used in solar thermal systems come in many different shapes and sizes and offer a variety of different options. The most basic controllers just have a differential control - this activates the solar pump when the temperature at the sensor on the collector is at a higher temperature than the sensor on the storage tank.

I have a 7 year old Solartwin panel on my roof which I believe is performing poorly and is not metered. The company say that the harder water is likely to be too much for the panel and that it needs an indirect panel. Thus I feel I need to replace it. It is a landscape shape high on my roof, now surrounded by PV panels, so its replacement needs to fit the same space. Given the space constraint, what is the best panel/system to install? I cannot easily find outputs per square metre gross.

There are two ways of installing a solar thermal system with a combination boiler. In both cases you will need a new hot water cylinder. This can often be the biggest problem as in most cases where a combi-boiler is installed, there is no room for a cylinder

I am often asked whether a solar thermal system can be used for space heating as well as for hot water.

Technically, it can. However in most cases it is neither cost effective nor energy efficient to do so. The cost of upgrading the system to work with space heating as well as hot water can be expensive.

A vital part of a solar thermal system is storage. The sun is not always shining when you need your hot water!

On larger systems molten salt is sometimes used as the storage medium for the heat. Generally however, the heat is stored in water, especially if the purpose of the system is to provide hot water.

Evacuated tube collectors are the Formula One of the solar thermal world. They are more efficient than other types of collector as they are almost perfectly insulated, and heat cannot pass through a vacuum. As the tubes are cylindrical, they are always perpendicular to the sun reducing the amount of energy that is reflected before it hits the absorber. They are capable of achieving much higher temperatures than other solar collectors as the vacuum ensures that no heat is ever lost.