The experience of being a teenager leaves a host of memories, of social awkwardness in the difficult process of not quite being a child any more, of tedious school days, and of team sports seemingly enjoyed only by the few. Wherever in the world you grew up will have lent a particular flavour to your recollections of that period of your life, whether your memories are good or bad.
One surprising common theme in British teenage memories, at least those of a few decades ago, are power stations. In the 1970s and 1980s, the Central Electricity Generating Board had a PR effort that involved bringing parties of teenage school geography students in for a tour of their local electricity plant, so if you talk to a British person of a certain age you’ll probably find they’ve been up close and personal with a coal-fired power station.
The true power station marvel of the age would have been too far away to tour for most kids at the time, though our geography teachers expounded on it at length. Dinorwig pumped-storage power station in Wales was opened in the early 1980s, and is a hydroelectric plant that uses excess grid generating capacity in the middle of the night to pump water into a lake at the top of a mountain, from which it can later be released at very short notice to respond to demand surges in a matter of seconds. The oft-quoted example is that when an episode of Coronation Street draws to a close there are several million British kettles turned on simultaneously, at which point Dinorwig comes online to rapidly make up the resulting shortfall.
We have all opened an electricity bill and had thoughts of saving a bit of money by generating our own power. Most of us never get any further than just thinking about it, but for anyone willing to give it a try we are very fortunate in that we live in a time at which technology has delivered many new components that make it a much more straightforward prospect than it used to be. Electronic inverters, efficient alternators, and electronic battery management systems are all easy to find via the internet, and are thus only a matter of waiting for the courier to arrive.
[Frédéric Waltzing] is lucky enough to have access to a 135 foot (38 metre) head of water that those of us in flatter environments could only dream of. He’s used it to generate his own power using a modestly sized but very effective turbine, and he documented it in a Youtube video which you can see below the break.
He brings the water to his turbine house through a 1.5 inch plastic pipe, in which he maintains a 55PSI closed pressure that drops to 37PSI when the system is running. His Pelton wheel develops 835RPM, from which a small permanent magnet alternator provides 6.3A for his battery management system. An Enerwatt 2KW inverter provides useful power from the system.
This hydroelectric installation might not be very large, but its key is not in its size but that it can run continuously. A continuous free 6.3A charge can store up a lot of energy for those times when you need it.
We’ve all been there – hiking in the woods with a dead phone battery. No GPS, no way to Tweet that selfie from some hill with a great vista. It’s a disaster! But not if you have access to a little trailside junk and have the ingenuity to build this field-expedient water wheel generator to recharge your phone.
OK, it’s a stretch to imagine finding all the things needed for [Thomas Kim]’s hack. We’re only guessing at the BOM – the video below has little commentary, so what you see is what you get – but it looks like a garbage can at the trailhead might at least yield the materials needed to build the turbine. Water bottle bottoms and a couple of plastic picnic plates form the Pelton-like impeller, the frame looks like an old drying rack, and the axle appears to be a campfire skewer. But you might have a hard time finding the electrical side of the build, which consists of a stepper motor, a rectifier, and an electrolytic cap. Then again, you could get lucky and find a cast-off printer by the side of the road. No matter how he got the materials, it’s pretty cool to see an iPhone recharging next to a babbling brook in the woods.