Developing Low-Tech Alternative Infrastructure: A Journey with Daniel Connell

My name is Daniel Connell. For the last 10 years, I’ve been developing low-tech alternative infrastructure. Basically, things people can make themselves from recycled, readily available materials which take care of their basic human needs. This is mostly to do with energy, water and sanitation, food, that sort of thing.

I’m currently at a place called Valldaura Labs in the hills of Barcelona, working with a group called COACT to develop a pico-hydro turbine. This is a very small-scale but very low-cost and portable means of producing electricity from water. The whole project has been open-source, making things more accessible. Theoretically, anybody anywhere can make the stuff and get access to these resources.

The Concept of Pico-Hydro Turbines

There’s a bit of optimization that is going to start rapidly paying off. So, we’re going to try again with two different approaches – a basic computer fan. Plan B point five is this impeller design which we’re now going to 3D print. This is the phase 3 turbine; it’s similar to the previous ones that we tested. I am going to flip it around direction-wise though, so that the water is going to come in from here but this will be on…

Testing and Optimization

So we’re going to move it further down the canal. It’s about a 2.2-meter drop instead of a 0.9-meter drop, which should give like three, three and a half times as much power overall. So the water’s going to come up here, go through here, across the top of the weir and then vertically down. This is going to be horizontal and then the water’s going to come up this way and turn the fan in that direction and then the pipe’s going to plug in here like before. Other than that, it’s basically the same.

So we’re going with the unreinforced PCU fan which did the best revs. The 3D printed impeller did a good job in terms of torque with fewer revs. I want more revs with less torque… I don’t want less torque, but I want more revs because that means more voltage, which means less transmission losses and stuff. Don’t worry, it’s only water. Well, water and some level of toxic waste. Water from the Anoia river. Wow. Holy shit, so fast! Super. There we go. That’s the number.

Power Output and Efficiency

If we can get 10 amps of this hoverboard wheel, which it should be rated to, times 55 volts, if there’s enough power in the full system, that means we could, without melting or damaging anything, be getting about 500 watts off this system quite easily. If there’s enough water flow, but there should be, because the full system power of this is about 1.2 – 1.3 kilowatts. So even if we’re only going at like 40% efficiency overall, which it’s hopefully more, that’s doing 500 watts right there. So that, times 24 hours a day is 12 kilowatt-hours, which is enough to run about two-thirds of a western suburban home. Everything here cost about 40 euros.

Real-World Applications

So, what we’ve got here in terms of water availability is quite good. We’ve got this long vertical drop, we’ve got a really solid water supply here. Most situations aren’t going to have something quite this good. This is a good situation, but it’s also a lot of power. In other places where they’ve got little streams that come down a couple of meters on an angle, this will do a lot less power but it’ll still do useful amounts of power. Especially if you’re camping, make a little portable version. Especially if you’re living in the developing world, the global south, then this, I mean… what’s coming out of this right now will power like, I dunno, half a dozen homes in a developing country. Easily.

And cost less there than it did here, because generally materials are cheaper. Like this is all very, very standard stuff. The hoverboard wheel, not so much, but everything else you can get anywhere in the world. This can get swapped out for a motorbike alternator, or something similar to that, which is available anywhere in the world and will do fairly similar amounts of power and voltage per rev.

Future Developments and Community Involvement

Next, we’ll wire it up. That’ll be on these guys here at Ca La Fou, to design a system for themselves, and like, do what they want it to do, wire it in, and then we’ll start getting some numbers, some data, and that can be broadcast. Once this has been going for a while, and as long as it doesn’t break, I mean we still need to burn this in, obviously over like days and weeks and months, but if it does all hold together, if it does seem like it’s a fairly optimized design, then I’ll be doing a full 3D animated construction tutorial on how to build the thing itself and then everyone can make one if they want one.

So basically, this is a very good result. This is a very good result. I’m pretty happy with this. All right, let’s see how easy this is. Yep, pretty easy. [Struggles] And there she goes. The previous test, the propeller was down the bottom and the water was coming down past it, which is generally how these things are done and feels more intuitively like how a turbine should be. With like a Pelton or a Turgo, like the more usual twenty meters, a hundred meters of head running a bunch of pipe and having like a jet of water onto a spinning turbine wheel, then you need to put the turbine at the end, obviously, that’s where the pressure is at the bottom.

Principle of Operation

But that’s not how this turbine works. This turbine works by getting as much water moving as quickly as possible. The pressure difference between the start and the end isn’t where the power is coming from. The power is coming from the momentum, so it’s more like a wind turbine in principle than a water turbine like a Turgo or a Pelton.