View Full Version : ROI - Self Sufficiency

12th Aug 2010, 04:43
With all the global warming / weather change / we're killing the planet type people running about we've got hybrid cars, solar panels, wind farms etc. but for a real impact we should be using this technology a lot more. Even if it is for a better cost of existence.

I look at my meagre existence in the world and think, "OK, let me spend less on power, I need a solar panel set-up. How much is one of them?" About $10K to be realistic. This will save me about $700 a year. A 14 year ROI and maybe I might even make a loss if I move house thereafter.

The same goes for any other 'money saving' type device, it costs so much to install them that it will take you way too long to get any benefit from them. So the simple answer is to reduce cost of these devices, the old economy of scale thing going on. If you make photo-voltaic cells cheaper then people will buy them and the cost will continue to come down.

So why don't the greens spend all their donated millions to create a profitable business model to produce all this equipment rather than all the costly questionable documentaries telling us we're going to have a baron planet by 2013 or 20-whatever.

I would go green(er) it if it makes sense (i.e. does not cost me all my hard earned$$) but it doesn't.

12th Aug 2010, 05:54
The only real way to reverse matters is to introduce compulsory birth control, since far too many anti-social people are having far too many kids.

12th Aug 2010, 08:09
When we built our own place in Ireland a few years back I put a geothermal heat pump and a seperate solar system in for hot water (vacuum tube system - not photo voltaic). 18K Euro, which included the underfloor array and manafold setup. I reckon I can never exactly work out exactly how much I was saving with regard to the geothermal portion, but I was saving a fortune with the solar panel. My figures worked out at a ROI of about 6 years. The one thing that used to piss me off was that on really hot days the solar system would have to dump the excess in order to prevent expansion due to steam. It would vent 200 litres of 85 degree water 2 or 3 times a day to the drain.

12th Aug 2010, 11:50
Looked at from an energy ROI - i.e. how much energy is needed to manufacture, install and maintain a photo voltaic system over its lifetime - there's a definite question whether in the UK it can ever payback. Such little matters as replacement of batteries, and the big questions on reliability of the electronics when made with lead free solder, need taking into account.

12th Aug 2010, 11:56
Cleanest drains in the area then Dubh??

12th Aug 2010, 12:24
It was out in the boonies....a few minutes later you could see steam coming from the septic tank 50 meters away. Outdoor hottub arrangement was the obvious solution though.

12th Aug 2010, 12:30
Outdoor hottub arrangement was the obvious solution though.
In the septic tank?

(Also hot-tub only available on 'really hot days' . . . :ugh: )

tony draper
12th Aug 2010, 12:54
Best to factor in the cost of a few firearms as well otherwise when society does collapse someone like me and my gang will come alone and take your house off you and throw you into the street.

12th Aug 2010, 16:56

Designed to last five years, apparently, during which time I doubt if it will have repaid its costs:-
BBC News - Largest tidal power device unveiled (http://www.bbc.co.uk/news/uk-scotland-highlands-islands-10942856)