I don’t know a lot with a FTP above 300w, and most don’t ride at FTP every ride. So I will guess the average Zwifter generate below 200w for a hour.
I was taking 50 Watts into the grid as a starting point. Assuming that your average cyclist might generate 200 Watts at the pedal. The lost 150 Watts would represent losses due to losses in the generator, powering fans etc and transfer to the grid.
Our indoor cyclist would indeed feel resistance as the generator is driven. Assuming generator efficiency is around 95%, our cyclist would experience 200W of resistance and would generate 190W of electricity.
190W minus your fan, laptop and losses due to transfer to the grid… you may have a little left. I need to find out how much power my fan uses!
Exert 200W on pedals.
Output with 90% efficiency drivetrain/generator - 180W
Minus fan (mine is 30W apparently) - 150W remaining
Minus laptop, turbo power supply etc - 50W remaining
I don’t run the fan at max power and the laptop/turbo power supplies probably do not draw the maximum value stated on them constantly. There would be losses in transfer to the grid no doubt but I expect you’d transfer 50W.
9 cyclists per house.
Do you also have lights on where you Zwift?
I really don’t think you would be at a positive when all is said and done.
I don’t generally have lights on but the main light in the room is a 5W LED I believe. This probably wouldn’t impact the calculation much.
It’s an interesting idea. Obviously if you ended up with positive value, it would be small but perhaps in the future the infrastructure will be in place, so any energy produced would feed back regardless of how small. It would be satisfying if we could harness the power of the 10,000+ people cycling right now.
I run 2 x 60w fans and one 130w fan. Currently all on mid level. In the summer I run 4 fans on full. Just to get rid of all the heat I generate. The human body is not very efficient in generating power. Most of our energy is turned into heat.
That sounds intense. I should imagine you’re putting down more than 200W too 
it’s all fun and games until you decide to zwift during a power outage and give the workers fixing the power grid an extremely mild shock 
‘extremely mild’ 
Another way of looking at it is; feed the 200W back to the grid, and that’s effectively 200W less you’re consuming. Making us more environmentally friendly.
It may be an idea which is more common in the UK. We have smartmeters which record what you feed back into the grid. Normally from PV panels, but also from domestic wind and water. I should imagine an indoor turbo is similar to a small domestic wind turbine.
What if instead of creating all these watts with our legs and then wasting them into the ether the bike trainer was a generator used to power the fan? Or maybe the electric just ran backwards into your meter (like roof top solar) and lowered my monthly energy bill lol
You can buy a bike dynamo, modify it to work off of your flywheel and then connect it to a battery. I had a friend who used a Schmidt Hub on his wheels-on trainer to power a fan many years ago,
Don’t see this happening, to put it in prospective, based on the model developed with ChatGPT, you would need 75 cyclists to run a house! LOL There is a reason why Power Plants exist…
Variables:
- Cyclist Power Output: 200 watts (per cyclist)
- Cyclist Workout Duration: 2 hours per day
- Household Energy Consumption: 30 kWh per day (average U.S. household)
Step-by-Step Calculation:
- Energy Generated by One Cyclist:Energy per cyclist per day=200 W×2 h=400 Wh (or 0.4 kWh)\text{Energy per cyclist per day} = 200 , \text{W} \times 2 , \text{h} = 400 , \text{Wh} , \text{(or 0.4 kWh)}Energy per cyclist per day=200W×2h=400Wh(or 0.4 kWh)
- Total Energy Needed by Household:Energy required for a house=30 kWh per day\text{Energy required for a house} = 30 , \text{kWh per day}Energy required for a house=30kWh per day
- Number of Cyclists Needed:Number of Cyclists=30 kWh0.4 kWh per cyclist per day=75 cyclists\text{Number of Cyclists} = \frac{30 , \text{kWh}}{0.4 , \text{kWh per cyclist per day}} = 75 , \text{cyclists}Number of Cyclists=0.4kWh per cyclist per day30kWh=75cyclists
Final Summary:
- To power a typical U.S. household (30 kWh per day) with cyclists working out for 2 hours a day at 200 watts, you would need 75 cyclists.
Considerations:
- This is for daily energy needs, not continuous power.
- Assumes ideal efficiency in converting human power to usable electricity (which isn’t 100% efficient in practice).
- Would require shifts for continuous operation.
Crazy! We are a 2 persons household, need 10 kWh per day (Austria). Are those 30 kWh including e-car?
You promoted me to actually go and check out my usage (I usually just pay the bill and don’t look). I didn’t look thoroughly and I’m not sure I want to admit numbers, but anyway for me (a household of 4, detached house near Toronto) we are are probably around the 30kWh number, less in winter, but I’m going to need some extra cyclists in summer to keep my AC running!
You got to standardize the data to be able to compare. Energy consumption for electricity and gas, when normalized by square foot/meter, is relatively consistent between North America and continental Europe.
The key difference lies in house size: the average North American home is nearly twice as large as its European counterpart. Additionally, North America’s energy independence -contrasts sharply with Europe’s reliance on imports (65% of energy is imported). Combined with higher taxes, Europeans end up paying nearly twice as much for electricity and gas while consuming energy for homes half the size of those in North America. Btw, the coffee is much better in Europe!
Ok, AC in summer is the killer.
I thought it’s not so hot in Toronto?
Ride on!
Not sure if it’s the design of the houses (as in it’s assumed they will have AC so they don’t bother designing them to stay cool or the fact there are huge swings between summer and winter and they can’t), the average summer temps according to my quick google search seem to be 17°C (low) to 25°C (high) although when I’ve tried leaving the AC off it get unbearably hot in the summer.
What if the fan was belt drive instead of electric?