# Average Wattage and Energy Bill

Hi,

I’m curious if the wattage output by the rider translates watt for watt compared to power consumed by the trainer, ceteris paribus.

For example: Average 100W for an hour 7 days a week or 700W per week. Would my trainer consume 700W of power from my house?

Thank you,

I’m sure someone could give you a hugely technical response to this. Persoanally I’d get one of those mains power meter/loggers to find out.

I believe the Power supply for my Magnus is about 18watts.

Output; 15VDC @ 1.2amps = 18 watts.

My experience with solar power tells me that often the power supplies don’t run at max.  So I would expect about 10 - 15 watts.

Thank you Jeffery!

It would make sense that the trainer would not draw more power than the power supply is able to…supply. Good news for the wallet…

A follow up question would then be, if the trainer draws an average of 15W, where is the rest of the 135W lost? Heat? Mechanical? Magnetic? I imagine this would all have to take place in the trainer.

Does the spinning weight allow energy to be dissipated over a longer period of time? This would only make sense when freewheeling.

Ah-ha! I was wondering why my energy bill was so inexpensive last month: my FTP is at an all-time low…

I assume you are having a bit of fun at our expense with this question?

This guy has hooked up his toaster to his trainer: https://www.youtube.com/watch?v=S4O5voOCqAQ

Is this the source of the “I’m toast” phrase?

I think the power draw of the trainer is just to power the ANT+/BLE transmission and a bit of shenanigans in the trainer to adjust some resistancy contraption.

I’m surprised its necessary to have to plug it on given the amount of power that flows into it via my furious pedaling. A Wattbike can be unplugged once you’ve got going.

I think there’s an opportunity for a company to produce a ‘green’ turbo that allows energy to flow into the grid to reduce your bills by a tiny amount.