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Find out what gadgets you might be able to pedal power

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

After an unpromising start, having to be bribed by her parents to learn to ride without stabilisers, Sarah became rather keener on cycling in her university years, and was eventually persuaded to upgrade to proper road cycling by the prospect of a shiny red Italian bike, which she promptly destroyed by trapping a pair of knickers in the rear derailleur. Sarah writes about about cycling every weekend on road.cc.

21 comments

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Gkam84 [9080 posts] 3 years ago
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I don't think I need say anything. I smiled though  4

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Sarah Barth [86 posts] 3 years ago
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Gkam84 wrote:

I don't think I need say anything. I smiled though  4

Are you being smutty again?

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londonplayer [620 posts] 3 years ago
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PS Just checked my own Bosch fridge freezer. It's 160 watts.

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Sarah Barth [86 posts] 3 years ago
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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.

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londonplayer [620 posts] 3 years ago
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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.)

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lushmiester [177 posts] 3 years ago
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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.

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Gkam84 [9080 posts] 3 years ago
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Sarah Barth wrote:
Gkam84 wrote:

I don't think I need say anything. I smiled though  4

Are you being smutty again?

Smutty again?  39 I really don't remember being smutty before  13

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  7

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londonplayer [620 posts] 3 years ago
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Gkam,

whichc article are you being accused of being smutty on?  39

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Gkam84 [9080 posts] 3 years ago
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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.

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londonplayer [620 posts] 3 years ago
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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.

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Gkam84 [9080 posts] 3 years ago
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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  19

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londonplayer [620 posts] 3 years ago
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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!

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londonplayer [620 posts] 3 years ago
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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?

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Gkam84 [9080 posts] 3 years ago
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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  39

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Simon_MacMichael [2448 posts] 3 years ago
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Professional cyclists and refrigerators.

 39

Best not go there.

 3

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Bez [588 posts] 3 years ago
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Look, if we're going to be pedantic let's at least get it right, eh?  1

"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.)

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brylonscamel [21 posts] 3 years ago
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"It can't take a steady 450W and just store up Joules somewhere for when it needs them."

.. how about a giant capacitor?

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notfastenough [3665 posts] 3 years ago
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Simon_MacMichael wrote:

Professional cyclists and refrigerators.

 39

Best not go there.

 3

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!

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Alan Tullett [1566 posts] 3 years ago
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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.

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Nick T [913 posts] 3 years ago
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Your electricity bill is only £200 for the year?! Who are you with??

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SideBurn [890 posts] 3 years ago
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Where can you get a 240v bicycle powered generator?