Bradley Wiggins could save £11 a year running his washing machine with pedal power

Find out what gadgets you might be able to pedal power

by Sarah Barth   September 9, 2012  

Pedal Power.png

Using the energy generated by pedalling a bike is nothing new - we've had the dynamo bike light since about 1895. But this rather cute infographic from MoneySupermarket shows just how much power a cyclist could put out, and put to good use, around the home.

An average cyclist could power a desktop PC, small television, or desklamp, it says, and Bradley Wiggins is (possibly uniquely) capable of running a washing machine at 500 watts per hour. Unfortunately it's beyond even the most powerful pedaller to run a fridge, which requres a whopping 700 watts per hour.

What's more, at that rate of cycling, Brad could be saving £11.67 a year by cycling for an hour a day. Look away now, sponsors. At that rate he could be paying off the cost of a bicycle powered generator (£260) in just 147 years.

The rest of the graphic makes for rather smug reading for those of us who are regular cyclists. The most energy efficient mode of transport in general use? Check. Oh yes, and you're one in a billion. A billion cyclists worldwide that is. Congratulations!


Image source: MoneySupermarket

21 user comments

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I don't think I need say anything. I smiled though Big Grin

Gkam84's picture

posted by Gkam84 [8873 posts]
9th September 2012 - 19:29

0 Likes

Gkam84 wrote:
I don't think I need say anything. I smiled though Big Grin

Are you being smutty again?

Sarah Barth's picture

posted by Sarah Barth [993 posts]
9th September 2012 - 19:34

1 Like

PS Just checked my own Bosch fridge freezer. It's 160 watts.

posted by londonplayer [671 posts]
9th September 2012 - 22:34

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I think fridges and freezers have variable wattage, alternating between periods of full energy use while the compressor is running, and then next to nothing when the compressor shuts off.

700 may well be the maximum wattage, whereas your table may have listed the average wattage over time, not the higher amount used when the compressor runs.

Just a theory; am no engineer.

Sarah Barth's picture

posted by Sarah Barth [993 posts]
9th September 2012 - 22:48

2 Likes

Sarah,

The more I read that infographic, the more errors I spot. They are confusing Watts (which is measured per second) with kiloWatts per hour.

My Bosch fridge is 160 Watts. Therefore, the maximum power it can use at any one second is 160 Watts. True, it's not always running at full pelt. But when the fridge has cooled to the correct temperature, it will run at even less power. A fridge that uses 700 watts would be five times the size of one found in a standard home.

Check some of the "references" they have quoted below. One is just from a Yahoo answers page which isn't even accessible.

(Interesting infographic though and please don't take it as criticism of your own article.)

posted by londonplayer [671 posts]
9th September 2012 - 23:07

0 Likes

Stuff wind turbines and photovoltaic cells at last a way the kids can earn use of their PS3 and genuinely help safe the planet. Excuses me I've just got to speak to a social worker about child exploitation.

THE ONLY WAY IS BIKE

posted by lushmiester [156 posts]
9th September 2012 - 23:29

1 Like

Sarah Barth wrote:
Gkam84 wrote:
I don't think I need say anything. I smiled though Big Grin

Are you being smutty again?

Smutty again? Thinking I really don't remember being smutty before Surprise

But what I was getting at was. I need say nothing because it was obvious to me that some of the things above were so wrong and it cost money to find and collate all the information......waste of money Confused

Gkam84's picture

posted by Gkam84 [8873 posts]
9th September 2012 - 23:37

1 Like

Gkam,

whichc article are you being accused of being smutty on? Thinking

posted by londonplayer [671 posts]
9th September 2012 - 23:49

0 Likes

For instance, the average house uses 3,300 kWh per year which works out at 9kWh every day.....So on average, the UK household uses 0.375kWh or 375 watt-hours every hour.

So if the figures just for the fridge were right, that would work out at 6132 kWh per year. I know a fridge would never be working on full power, every hour, of every day. So even if you take it to half. Thats only slightly under the average UK household's YEARLY usage of Electricity.

Gkam84's picture

posted by Gkam84 [8873 posts]
9th September 2012 - 23:50

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Gkam,

Is this your area? ie are you an engineer or related profession?

It looked wrong to me when I saw that a washing machine used less power than a fridge.

posted by londonplayer [671 posts]
9th September 2012 - 23:55

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londonplayer wrote:
Gkam,

Is this your area? ie are you an engineer or related profession?

It looked wrong to me when I saw that a washing machine used less power than a fridge.

Slightly, I'm just a geek though. Was a bit of a maths and science genius at school. But seen as I was a drop out and had no qualifications. I became a chef.

Still a geek Devil

Gkam84's picture

posted by Gkam84 [8873 posts]
10th September 2012 - 0:02

1 Like

The other statistic that is wrong is that " a washing machine is 500 watts". I'm pretty sure when I looked at the technical data on the back of my w/m, it's about 2,000 - 3,000 Watts. Which would also mean that Bradley couldn't power it.

If you're going to produce an infographic, Moneysupermarket should at least get it checked by someone who knows!

posted by londonplayer [671 posts]
10th September 2012 - 0:12

1 Like

Unless they're running a commercial large fridge, I think they've got the figures for that badly wrong.

I've just checked on Bosch's website and a fairly large domestic refigerator, with freezer (therefore more energy consumption), is about 150 watts.

Any engineers here?

posted by londonplayer [671 posts]
10th September 2012 - 0:15

0 Likes

Yes your machine may say that, but just take for average that you have a 240v 2400 Watt machine

Average cycle (2400w heat and wash, 500w spin, 34w pumping)

Thats just going on the first manual that came up in my google search

http://samservice.com/resources/pdf/B1085-1285-1485_user-manual_EN.pdf

So that cycle, I think would be worked out on an hourly basis. But using the machine for say a two hour cycle. It may only use around 900 watts. So 450 watts per hour.

Thats not far off what they have calculated.

But their fridge seems way off, as 700 would be on FULL POWER, every hour of the day. I THINK the average fridge would run around 15-20% on a constant if you left the door closed. If you open it and let enough heat in. The compressor kicks in and the wattage goes up. When the compressor is going. Its on FULL POWER. But it is NOT going to take an hour to cool down a fridge Thinking

Gkam84's picture

posted by Gkam84 [8873 posts]
10th September 2012 - 0:25

1 Like

Professional cyclists and refrigerators.

Thinking

Best not go there.

Wink

Simon_MacMichael's picture

posted by Simon_MacMichael [8127 posts]
10th September 2012 - 0:39

0 Likes

Look, if we're going to be pedantic let's at least get it right, eh? Smile

"They are confusing Watts (which is measured per second) with kiloWatts per hour."

They may be getting some things confused, but kW/h would be a unit for rate of change of power (and a bizarre one at that).

"So that cycle, I think would be worked out on an hourly basis. But using the machine for say a two hour cycle. It may only use around 900 watts. So 450 watts per hour."

You mean 900Wh (Watt-hours), or more normally 0.9kWh, not 900W. And you don't mean "450 watts per hour", you mean an average of 450W for two hours.

Take your washing machine that uses 2.4kW for part of its cycle. To get it through that phase of its cycle you're probably going to need to put out roughly 2.4kW. It can't take a steady 450W and just store up Joules somewhere for when it needs them.

So although in two hours you might be able to produce enough *energy* to enable a two-hour washing machine cycle, you can't produce enough *power* to enable it.

(Think of it like a bike - you don't get to pedal at 50W for twenty miles and then suddenly blast through the air at 80mph for 30 seconds with the same low power output.)

Bez's picture

posted by Bez [382 posts]
10th September 2012 - 13:17

1 Like

"It can't take a steady 450W and just store up Joules somewhere for when it needs them."

.. how about a giant capacitor?

-- Hey, how many gears have you got? .. Just one! ... Mate, your bike sucks! --

brylonscamel's picture

posted by brylonscamel [20 posts]
10th September 2012 - 14:09

1 Like

Simon_MacMichael wrote:
Professional cyclists and refrigerators.

Thinking

Best not go there.

Wink

It's like the chicken and the egg - you need to be fast enough to power the fridge, but you need the fridge to make you fast enough!

Last night I would have considered trading a very loud baby for a really nice bike.

posted by notfastenough [3208 posts]
10th September 2012 - 14:26

1 Like

The whole problem with this is not the wattage of a fridge, which I agree they've messed up a bit, it's the cost of food. The energy needed to power a bike-generator has to come from somewhere and where it comes from is food. Food is actually quite expensive as a fuel for producing electricity. I'm quite sure that a human powered generator is terribly inefficient economically. My electricity bill is about £200 for a year for a family with more than its fair share of appliances. I hate to think what the cost of that powered by a bike would be? GINORMOUS. Probably bankrupt me and my food bill is already massive (in spite of using Aldi for most basics and cycle stuff - recently got heart montior for £13 and some compression underwear (top and bottom) for the same, so good I got another pair) as we like to eat well.

Even apart from the cost of maintaining a bike, new tires etc there is also the cost of food when commuting, so biking to work is not free, as people often claim, but if you use some cheap carbs for fueling the ride it's probably cheaper than a car!! Going on a longer ride depends a lot on the cost of the food you use to fuel it. Going to a Michelin star restaurant for 3/4000 cals might make for a pricey jaunt. Lots of homemade flapjack (or Aldi premium bars) and some sandwiches will see you through on a budget.

But cycling is not free and depending on your tastes in bikes and food not necessarily cheap even.

posted by Alan Tullett [1455 posts]
10th September 2012 - 20:53

1 Like

Your electricity bill is only £200 for the year?! Who are you with??

posted by Nick T [814 posts]
13th September 2012 - 7:32

1 Like

Where can you get a 240v bicycle powered generator?

posted by SideBurn [808 posts]
13th September 2012 - 13:30

1 Like