Solar companies which survey by phone and use aerial photos where possible, rather than by driving to make a site visit will result in your panel having a lower initial “carbon debt” to repay before it goes into carbon credit.
The use of unnecessary packaging for solar panels and their components should be minimised. Where it is used, it should be of recycled origin, or easily recyclable.
It may be environmentally preferable to re-use hot water cylinders. Many old cylinders contain CFC gases in their insulation foams. CFC’s damage the ozone layer. The UK is failing to enforce the EU “fridge mountain directive” upon used hot water cylinders. The result is that when some cylinders become squashed, either in landfill dumps, or during copper recycling, these CFC’s are released to pollute the atmosphere for decades. Solar heating technologies which may permit re-use of existing hot water cylinders may be environmentally preferable to those which always require new cylinders, since new cylinders have several negative environmental impacts. These can be associated with their manufacture as well as with the disposal or recycling of the cylinders which they replace.
To counter this down side of cylinder replacement, there are two counter-arguments. One is that some new hot water cylinders may have larger heat exchangers for the “boiler circuit” than those that they replace. This may offer a slight increase in “summer hot water boiler efficiency”: however this benefit is likely to be small given that solar reduces boiler use for water heating most of all in summer. The other is that new solar cylinders can be larger than what they replace, and so they can offer the potential to “iron out the bumps” between sunny and gloomy days rather better, due to their larger volumes.
Solar keymark certified
Micropower council
Renewable Energy Association
Association for Environment Conscious Building