I have long wondered how manufacturers can claim that their hybrid cars are eco green when they need not only liquid fuel but also electricity which they, the manufacturers, seem to forget about when doing the eco chart.

When visiting showrooms and asking for the comparison charts for fuel consumption there is always a vague reference to the fact that electricity is a renewable source so does not need to be counted in the emissions chart? So if I now put an extra battery (or three) into my car, change my engine to run on petrol and electricity I reduce my carbon footprint? Is it me or have I missed something here? The electricity still has a carbon footprint some say higher that of petrol engines due to the way electricity is produced. Coal and gas have a high footprint, as does transmitting the electricity to our homes where an estimated 40% is lost as it travels along the cables. That is another story to come back to soon.

There is a way of making the car greener and that would be to have a wind turbine or photovoltaic set of panels to charge up the car. If, as we are led to believe, a group of scientists have developed a panel that can produce up to 80% more electricity than panels used at the moment it should be easy to keep the carbon footprint down, even if sometimes the mains are used.

Now here is a thought; rather than shouting about the free energy would it not be better for the manufacturers to either have a built in solar charger or sell the car with a portable solar unit. I am not a fan of wind power because of the irregular supply they offer – one day I hope to change my mind.

A new product is being developed in the USA named the Solarial. It is a large airship that has the top layer of the balloon covered with photovoltaic cells to provide a supply of electricity to a power unit on the ground. In addition to this is a reversible propeller/wind turbine that again will provide clean energy to people on the ground. With so many people in the world in disaster zones, this would be a great way of providing relief energy and a communication link for the victims below.

Unlike other airships, the Solarial is filled with hydrogen rather than helium gas that is heavier, more volatile, and fast running out. Hydrogen is a renewable gas that will also fuel the hydrogen power cells designed to continue providing power at night or when the sun is low. The lower part of the airship has two dilation panels that expand as fuel buffer zones. Unlike other airships that have deaths associated with them, including the Zeppelin, this is an unmanned ship that can be inflated and put to use within hours to provide clean energy to victims of disasters.

Designed by Andrew Leinonen as a solar powered power station for an undergraduate industrial design thesis he won a first place prize in the 2008 ACIDO rocket show. Work continues on making the prototype ready for field test later in 2008.

Not one to stand by and suggest to readers the use of sun tubes that I have taken the plunge and had one installed. The builder, Nigel, arrived with his son and looked at the box, read the instructions and then said “ never put in one of these before” A challenge for him but the section of roof was off, hole cut through the battens then the ceiling. The fixing instructions were easy to follow and the tube fitted within three hours. What a great way of introducing natural light into a dark area – the sunsets through the tube are wonderful. The tube used can be unhooked from the ceiling light to double up as a light for working in the attic space. What has been great is the number of people who have been in to see the sun tube and now plan to install one or two in their own homes. If it carries on I think I may start charging to see the sun tube – or as it was referred to, the sun pipe. There are many versions on offer so pick one that suits your roof type and the amount of light you require. Have a look at the model specifications on the manufacturers or suppliers web site. Prices range from £300 installed, which is not cheap, and will take a long time to recoup the outlay yet I feel it was money well spent. It also means I can now look to get prices cut or come up with a DIY option to reduce costs.