Home Power Generation - Can You "Sell" Energy Back to the Grid?

[rickrock]

Hi,

I am from the uk and very interested in home power generation. I am aware that there is a system that you can install in the home which will 'sell' excess power back to the grid if for example you are running a wind turbine which produces more electricity than your home requires.

In principle, could you setup a bike whereby pedalling will 'sell' energy back to the grid? I know that this energy production would be very small, but when I look at even medium sized wind turbines, it seems that the energy required to make the necessary revolutions of the wind blades turning a dynamo could be done using a bike chain/peddle setup by a reasonably fit person? I say it seems so but I am guessing I am making a grave miscalculation here although I'd like someone toexplain to me why.

However as I said, would it in principle be feasible to make such a setup with a modified bike to 'sell' power back to the grid, no matter how small? What would be the main technical difficulties in making such a system? If anyone knows of some relevant resources I'd appreciate it.

 

[sid_galt]

In principle, could you setup a bike whereby pedalling will 'sell' energy back to the grid? I know that this energy production would be very small, but when I look at even medium sized wind turbines, it seems that the energy required to make the necessary revolutions of the wind blades turning a dynamo could be done using a bike chain/peddle setup by a reasonably fit person? I say it seems so but I am guessing I am making a grave miscalculation here although I'd like someone toexplain to me why.

In principle you could generate electricity using a human run bike wheel but you wouldn't generate enough electricity to power a light bulb. Practically unfeasible.

 

[russ_watters]

Have you ever used an exercise bike, rickrock? Most electronic ones tell you how many watts you are generating. If you're Lance Armstrong, you may be able to generate 200w for a few hours, but even that isn't enough to be worth doing.

 

[berkeman]

I think our local power company (PG&E) has restrictions on how little you are allowed to transmit back into the power grid, but I'm not certain about that. I also think that coupling power back into the grid is not generally possible at 100% efficiency, so the losses would likely dominate for a small generator like 100W. I googled PG&E and Cogeneration, and got to this fairly useful page:

http://www.pge.com/suppliers_purchasing/qualifying_facilities/

BTW, speaking of wind turbines and power generation, I always wondered how they combined the power output from multiple windmills spinning at different speeds (due to wind speed variations). I wrote a letter to our local newspaper's answer column, and got a very interesting reply. It turns out that all the windmills in a farm will spin at the same speed -- they are locked to the 50/60Hz power grid, and they contribute varying amounts of power to the grid, based on the local wind speed. We have large windmill farms nearby east of Livermore, California, and when we drive by them now, it's obvious that they are all locked together. Pretty interesting.

 

[Cliff_J]

rickrock - why not just start this up in your own local gym and now people would pay you to use the bicycles and you might save 5-10% of the electric bill from the generated power.

We as humans don't really generate much power. Some science show was talking about having pedals in an electric car so the passengers could generate electricity and exercisd. Too bad it could easily be outperformed with a photovoltaic cell on top the car, and now you'd really want one of those gaudy air fresheners hanging from the rear view mirror.

If you don't believe us hook a car alternator up and have it power a regular 60W automotive headlight (with the alternator you'll need an inital 12V battery hookup to get it generating power unless its a one-wire alternator). If you're in good athletic condition, maybe 3-4 hours for less than 1/4 a kWh, which at 10 cents/kWh is just over a couple pennies American money.

 

[Ouabache]

The concept of using a bicycle to generate power is really not that far fetched. I remember reading a book called Pedal Power, that described pedalling a bicycle to power such diverse applications as a drill press, washing machine, a grinder, TV/VCR, generator, to saw wood, pump water, split logs, and press cider.
Here is another related link on human power

 

[Pengwuino]

I remember Ivan saying that a human body can create around the area of 100W.

Lightbulb here i come!

 

[spongebob_79]

Im not sure, but i think to enable the grid to accept electricity, it may have to be a certain frequency/phase i think.

I like the idea for the gymnasium though :-)

 

[Integral]

Have you ever used an exercise bike, rickrock? Most electronic ones tell you how many watts you are generating. If you're Lance Armstrong, you may be able to generate 200w for a few hours, but even that isn't enough to be worth doing.

I have always dreamed of hooking up the kids game system to a battery and a bike. If they want to play they have to charge up the battery first. Get their exercise and play as well.

 

[Danger]

I know of someone who did that with the TV set. The kids quickly learned to weed out the shows that they didn't really care for. (They could 'bank' the power in batteries, so they didn't actually have to be pedalling while watching.)