PowerSwitch

Dick Strawbridge in the Guardian on 27 May wrote:1) Environmentally friendly installation is expensive

All insulation is environmentally friendly. Some installation has better environmental credentials, but what matters is the energy it saves. There is something nice about insulating the loft with reused sheep fleece, or recycled bottles, but if the cost of the insulation is putting you off doing it don't think twice: buy the cheapest. Some stores have sold insulation as cheap as £1 a roll in the past. All insulation takes energy to make it, but that is not a reason not to invest in it. The savings, for both the planet and the bank account, can be impressive. Incidentally, you need about 270mm of insulation in your loft which is about a foot deep — anything less and you're wasting valuable heat.

2) The UK is not sunny enough for solar power

For a nation that spends a lot of time talking about the weather, we don't seem to realise just how much sunshine we actually get. Maybe that's because we tend to concentrate on the negative aspects. Every square metre in the United Kingdom has on average about 1,000W of solar energy incident on it every day. That's an awful lot of free power. Without getting too technical, a 1,000-watt photovoltaic system can be expected to produce 1,200kWh a year, an average of nearly four hours working at maximum power a day. Obviously, it's much more productive in the summer, and there are lots of days when it is not frightfully impressive, however, let's not forget we do get some lovely sunny spring, autumn and winter days. Even in the winter, my home's solar thermal system (that uses the power of the sun to heat water) is capable of harnessing the weak winter sun to preheat the water in our hot water tank.

3) Wind turbines only function on hilltops

I fully understand the physics and know that "laminar" airflow, or streamline, is what every wind turbine loves. In theory a wind turbine on a mast in the middle of a vast plain will give the best performance, but there are not too many locations that fit that bill. So we have to compromise. Most importantly, to get good performance from a wind turbine, it is necessary to have no obstacles near it that will disrupt the airflow. A built-up area with houses, hedges, and trees is a long way from the ideal location. However, if that is where you live and you want a wind turbine you don't have a lot of choice — and a turbine will still generate electricity in such a setting.

4) Most eco-renovation take decades to pay back the cost

Every time we decide to make an investment in an eco-project, the subject of payback comes up. It is possible to do the sums, and before we spend any hard earned cash I like to make sure that it's a good investment. For example, loft insulation can pay for itself in two winters, and with the 2010 feed-in tariff I would expect solar PV to pay for itself in about seven or eight years, and a DIY solar thermal system to heat your hot water should have paid for itself in four or five years. But surely this is missing the point: when it comes to environmentally friendly projects we seem unable to accept the fact that it can be an investment and will add to the value of the house. What is the payback time for a new bathroom or kitchen? If you install solar photovoltaic panels you can reasonably expect them to easily last 25 to 30 years. Everyone knows a new kitchen makes a house more saleable, but in the current economic climate, how much more saleable is a house that will cost the new owners very little to run or may even generate an income?

5) DIY loft insulation is horrid and itchy

It's a fair cop, installing fibreglass or rockwool insulation is not the most pleasant job in the world, but if you are installing your own loft insulation why choose fibreglass or rockwool? There are lots of alternative insulations that are very benign and easy to handle. You can now buy loft insulation that is made from high-tech composite material, recycled plastic bottles, hemp… the choice is almost limitless. Indeed, in our loft we have Thermafleece at one end (made from the fleeces of upland sheep that in the past has gone to landfill), and insulation made from recycled denim at the other. Lots of these materials are easy to lay and relatively pleasant to handle. However, we do have to face up to the fact that working in the loft is not the most pleasant of environments so, no matter what you sort of insulation you choose, you will end up being a bit sweaty and dusty!

6) It takes more energy to build a solar panel then it will ever create

This particular misconception has been doing the rounds for several years. It is fair to say that it takes a lot of energy to make photovoltaic panels because it is a complex crystalline structure. Depending on the type of panel it can take between two and four years of use to recover the energy needed to make it. That said, the efficiency of the modern solar panel and modern manufacturing techniques are improving every day. There are no moving parts, so it is reasonable to expect the PV panels, which are usually guaranteed for 25 years, to last an awful lot longer (some of the older ones have been going for nearly 40 years).

7) Eco-gadgets are cons

It would appear that the green revolution is a marketing man's dream. Everywhere we go there are eco-gadgets that claim to be saving the planet. Most eco-gadgets tend to be quite complicated. Wind-up and solar-powered radios, battery chargers and numerous small electronic devices, are usually marketed as being cool. It is fair to say that they are extremely useful if you do not have access to another power supply (which does not happen very often in today's world). So, if you find yourself in a situation where only an eco-gadget can save you they are definitely not a con. However, from an environmental standpoint, to justify the embodied energy it takes to produce them they have to be used a lot rather than being kept in a drawer full of other cool things.

8 ) You have to be an engineer to undertake your own eco home projects

In the 21st century there is no excuse for not being able to get stuck into any eco-project. Information is readily available and all the materials you need can usually be sourced within 10 miles. Of course, I have to acknowledge that there is some sensible legislation that means you are not allowed to fiddle with mains electricity, or get involved with structural engineering, unless you're suitably qualified. That does not mean you can't do most of the work yourself, which is by far the cheapest way. There seems to be a certain reticence when it comes to starting a project and a lot of excuses rather than reasons out there. If you have running water and a desire to have a water wheel, all you need is to know that the angle of the bucket is 114°. With a little bit of common sense, anything is achievable.

I have had enough 'leccy to do a hot wash

woodburner wrote:It gets abit dumb though if the energy taken to make the equipment is greater than the amount it saves, unless you use the car comparison though, I suppose.