The True Cost of Powering a Light Bulb for a Year

[Gotwind Ben]

Most interesting, a (Generated) power comparison.
http://www.treehugger.com/files/2010/12 ... t-bulb.php

Full image here (It's big) http://awesome.good.is/transparency/web ... /flat.html

I'm not completely sure the sources of power are totally comparable however.
Phrases like 25% efficiency, 80% capacity??, these are just assumed I suspect.

One for 'Fish' to lend his mathematical mind to I hope ;)

Treehuggers comments may also help get some 'truth'/ clarity from this.
http://www.treehugger.com/files/2010/12 ... p#comments

Interesting find Ben, thanks for sharing it with us.

On the whole it's a great idea to demonstrate to people just how much energy we use.

However, the figures are a little misleading. For starters, how many people still use 100w lightbulbs these days? and how many people leave them on 24/7 for a year? Also not sure where they get 20-25% efficiency from for the solar pv. Even taking this into account, I like the infographic, it helps people understand just how much energy we use.

I think that to really get the message across to people you do need to put it into terms that they are familiar with and understand.

My favorite is that it costs around £9 per year to run a single 50w halogen bulb.

Many people these days have 50w downlighters and they certainly understand money....

Sorry I missed this one back in December.

I don't have any real problems with any of the math on the page:

25% capacity means that the 1.5MW Wind Turbine over the course of one year might have an annual output of 25% of its rated capacity, hence producing a total of 3,285,000kWh. (As opposed to 1,500kW * 24 * 365 = 13,140,000kWh) We should all hope we build a wind turbine that achieves an average output of 25% it's rated output over the course of a year!

339kW Hydro Operating @ 80% efficiency is a bit less straight-forward, but the point is there is 20% more energy in the falling water than the turbine is capable of turning into electricity. While this is an odd way of stating things, it is, none-the-less on the optimistic side of accurate. It is combining the conversion efficiency of both the turbine and the generator into a single term.

Fish