I think I've heard/read more than once that the average competition-level cyclist produces 1/3rd horsepower. I don't remember how many watts that converts to, but am inclined to guess it's in the 400 watt neighborhood.
Through careful selection of lights and pump, the koi pond in my front yard uses just over 200 watts at night when both the pump and lights are running.
So another way to look at it is that if I pedaled a bicycle/generator for 8 hours, I might just make enough juice to handle 24 hours of power requirement for the koi pond.
While on the subject of alternative energy (a HUGE passion of mine), I'm in the beginning throes of enlarging the lake behind the house so it can produce enough power to run the lights (about 4-5KwH of them) in my workshop. By my calculations, I can run a lot more than the lights. Perhaps all the 120-volt outlets as well. Don't want to buy a big enough inverter to run things like the lift and welder. The conservative estimate is that I'll be able to make 2KwH nearly year-round from the lake while also having the benefit of preventing the occasional flooding that's happening downstream from me. Keeping in mind that I might run my lights for about 20 hours per week, at most, there's a lot of excess juice available if I'm making the 2KwH I expect. The plan is to have enough batteries to store about 10KwH (4 hours of lighting, keeping in mind the genny would still be contributing while I'm draining the batteries) then shunt any excess capacity off to other loads like pumping from the lake to the ponds, running a water heater, etc.
Right now the weather isn't cooperating. Two times this week I've spent about 15 minutes digging the creek deeper to help it drain better to help dry out the surround soil/clay mix I'll use to raise the dam while also deeping the lake, and each time I've spent 1-3 hours getting the backhoe unstuck. I've searched, in vain, for an upstream area for a temporary dam to get the rest of the lake to dry out more quickly, but there's nowhere I can make one that'll contain even a moderate rain.
In most areas, it looks like I can dig out a good 8 extra feet of depth, and we've carefully measured and found that we can raise the dam an additional 8 feet and still leave the water level a relatively safe 5 feet below bottom of the bridge over the creek feeding it.
We should be able to keep a good 16-20 feet of head at the generator and flow as much as we want. And will make the flow very adjustable, with a very generous top end since we'll want to drain the lake down quite a bit in advance of the occasional gulley-washers we get.
On another alt-energy note, in addition to the work on the lake, which may take a year or more with my limited time and windows of opportunity, if I ever have funds and time, I've got a huge pet project that I think could really be interesting.
My car hauler has 48x8.5 feet of roof on it. You can get a lot of solar panels on that kind of roof.
What I'd like to do is cover the roof with solar panels, put plenty of batteries in the belly of the trailer, and at least a 20-horse electric motor under it, replacing the front axle with a truck rear-end, which would be driven by the electric motor.
My son will have to help me with this design and the calculations involved, but my goal is to build a system that'll have the trailer doing 20 horses worth of its own pushing on the 3 1/2 hour trip to and from Omaha. It'll be a challenge to come up with an idea of how much battery storage will be needed to have it and the panels (and possible regen braking) do that kind of output for 3 1/2 hours under a noon sun and 20 horses may be unrealistic. Might have to start with more like 5 horses and work our way up if we've got the juice for it.
It'll cost a lot more than it'll be worth, but that's beside the point. The initial goal will be (assuming I don't trade in on a semi by then) to achieve 20 mpg (best so far is 8.5) on that trip and once we've got the electric side of the equation nailed down so that we're storing and using as much electric power as possible and getting all the fuel economy boost we're ever going to get from the setup, then explore other options. Streamlining. A super-efficient helper engine (Yanmar turbo-diesel -- perhaps to power a genny rather than spin tires). Things like that.
Truck, trailer, and load come in right at 25k lbs. And batteries will likely add 1-2k lbs to it.
If solar panels ever get reasonably priced (they might, with Honda entering the market), and the setup proves effective, the same design would be a no-brainer to apply to semis.
All I need is available time and money. No telling when I'll have either. But, aside from the very high cost of these kinds of electric motors, the rest of the money can be spent a little at a time. Just a couple of solar panels and a few biggie batteries, and see how long the batteries hold up on the KC/Omaha run.
I'm hoping my retirement comes while I'm still young enough to devote the rest of my life to playing around with alternative energy.
