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I can't imagine where you are getting this information, it's just not true. Energy payback for most solar installations is less than 4 years, well within their service life. This includes inverters and mounts. Even financial payback, once not possible, now is a given.

From what I understand, you can expect a MTBF of 10-20 years or something like that and then they are garbage.

Where did you get that idea from? The inverter needs replacing in that time frame, but most guestimates I've seen of PV panels are that they will stlll be good for most of their energy output after 40 years. E.g. this page: http://info.cat.org.uk/questions/pv/life-expectancy-solar-PV-panels

The warranty conditions for PV panels typically guarantee that panels can still produce at least 80% of their initial rated peak output after 20 (or sometimes 25) years. So manufactures expect that their panels last at least 20 years, and that the efficiency decreases by no more than 1% per year.

http://www.cat.org.uk/

sorry, I posted anonymously by error.
Data on sustainable houses and buildings available from C AT, Centre for Alternative Technology, with examples built already on their mountaintop in Wales!

There are several hard problems in wind turbine design. One is that, for large wind machines, wind speed may vary considerably across different parts of the blade area. This produces huge stresses in the blade system. Aircraft propellers and hubs don't have that problem, so technology borrowed from aircraft props didn't quite work. That's been solved, but it took years to get past it.

A basic problem, one which this new design doesn't solve, is overspeed protection. Wind turbines above toy size must be able to deal with high wind conditions safely. Some turn sideways; some turn upwards; some feather the props. Brakes aren't enough. There's no way to feather or turn this new design. Even small turbines need, and have, overspeed protection.

There are lots of wind machine designs that more or less work in a small size, but don't scale up to the point where they're worth building. There's a square law; double the blade length and get four times the energy out. So big turbines beat out little ones, once ths scaling problems are solved. Wind turbine size has been creeping up since the 1970s, from about 50KW to a few megawatts.

A 1.5 MW unit was built in the 1940s, but it suffered a bearing failure within a year, then a loss of blade accident which threw a blade 700 feet. Only in the past decade have reliable wind machines in that size range been produced in quantity. With 2800 of their 1.5MW units installed, General Electric can be said to have solved that scaling problem.

The big machines aren't simple. They have active yaw control, active pitch control, hydraulic brakes, AC to DC to AC variable frequency conversion, and lightning protection. But, at last, they work.

So these guys are going to beat that with a little tin model that looks like something used to spin a sign in a used car lot. Right.

I grow alot of my own food organically. This has got to be the ultimate reality hack getting stuff to eat from playing with dirt.

the ways used to combat pests (slugs are a problem in our damp climate) and the deludge of water in the winter and total lack of water in the summer are pretty cool hacks that are age old.

I have an automatic watering system that stores rain water and during dry spells automaticall waters. The windows on my greenhouse open automatically when it gets hot. And compost, compost is the best age old hack we wouldn't be here without composting ;-)

We also make the majority of our own bread and have recently stopped making wine and beer due to changing drinking habits as I past 30.

Green hacking is the way to go. Just look at all the ways people are getting wired off the grid. my personal fav resource is the centre for alternative technology and home power.

You can teach anyone to play with computers but getting them to play with computers, garden, bake and brew is a the sign of a real hacker ;-)

sparkes

I don't see why out-of-print material should still be subject to copyright. Now we're in an age of digital printing, there's no reason at all for information to become unavailable - if the publisher still wants to profit from it, they should make it available, but why should they get to keep a copyright if they're not going to use it?

But then there is another story not many people remember about someone doing work on creating a pump mechanism that you place in a river. Using the kinetic force of the movement of the water to power a pump to take some of the water from the river and push it thorugh a hose up a hill. This was a device that was just submerged in the water without the need to dam the river.

I'm not surprised that not many people remember it. What you have described is a hydralic ram, which was invented by the Montgolfier brothers (of ballon fame) in 1793. See here for the details.

...are nothing to sniff at, though given the state of some of our schools one has to wonder about the posible motives. Anyway for more info on a broad range of building techniques and other alternative stuff take a look at these guys: Centre for Alternative Technology. They have some rather impressive buildings made from a range of materials. Including a Straw bale theater and a new visitor center made from rammed earth columns.

...are nothing to sniff at, though given the state of some of our schools one has to wonder about the posible motives. Anyway for more info on a broad range of building techniques and other alternative stuff take a look at these guys: Centre for Alternative Technology. They have some rather impressive buildings made from a range of materials. Including a Straw bale theater and a new visitor center made from rammed earth columns.

...are nothing to sniff at, though given the state of some of our schools one has to wonder about the posible motives. Anyway for more info on a broad range of building techniques and other alternative stuff take a look at these guys: Centre for Alternative Technology. They have some rather impressive buildings made from a range of materials. Including a Straw bale theater and a new visitor center made from rammed earth columns.