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Is there a database/webpage/other source for obtaining simple, easy to understand and meaningful equivalents for converted energy by a photovoltaic-site (Wh/kWh/MWh/GWh)? Something like "xxxkWh equals watching the superbowl on a lcd screen for 1 hour"? Just simple stuff, not too technical - for the non technical mere mortals so to speak.

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The Register will convert units into Reg units for you. They haven't yet included a conversion for GigaJoules to circumnavigations of the earth by a blue whale yet, but have patience. –  RedGrittyBrick Dec 5 '12 at 16:38
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4 Answers

up vote 2 down vote accepted

It sounds like what you're really getting at is a way to make the oft-quoted performance numbers for various electricity generation options (PV included, of course) more understandable to non-experts. Having spent a few years teaching this material, I find that the right approach is to do more than simply quote the fact that X familiar object uses Y power or Z energy. My experience has been that 'aha' moments come about when folks develop a framework for understanding the role of energy in their lives so that they can compare among all its different uses and sources.

David McKay's book Sustainability Without the Hot Air, which is available for free here , does a spectacular job of helping the average person understand the energy system. The quick reference section at the end has some of the information you explicitly asked for, but if you want someone to really get it I recommend having them read the first two chapters and then the chapter on any technology you want them to understand (solar happens to be chapter 6).

The best quick reference I can think of for data on familiar objects (both power consumption and what you get for a 1 kWh), is this visualization prepared by GE.

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+1 great reference –  user2963 Feb 7 '12 at 22:00
    
Thanks for the reference! Since the information is presented on a dashboard style webpage, what I need is quick, but nonetheless easy to understand energy conversions. Thinks of it like you are walking by a tv screen and read the examples - unfortunately there is not much time to read! Sounds like you are a teacher or at least experienced with teaching people, do you have more advice? –  junior Feb 8 '12 at 7:31
    
+1 It's a flawed book, with a lot of mistakes in it, but it is a lucid introduction to the subject –  EnergyNumbers Feb 8 '12 at 12:24
    
I just remembered that GE put together an interactive visualization meeting your requirements. I've added that to my answer. –  sevenofdiamonds Feb 8 '12 at 19:51
    
Cool visualization, I will try to extract the most meaningful values from it. If you have any other examples feel free to visit again and add them. –  junior Feb 9 '12 at 6:44
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A unit of electricity (in most countries) is a kilowatt-hour, ie a 1000 W appliance running for 1hour, or a 100W appliance for 10hours.

Typically a regular light bulb (if you still have them) is 100W, a big screen LCD TV is about 250W and an air conditioner or furnace will be between 3000 and 10,000 Watts

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Chart here absak.com/library/power-consumption-table –  Manishearth Feb 7 '12 at 17:17
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Let's look at the amount of energy (in Joules) in one second - i.e. in SI units of power, Watts: that way, you can directly compare between them, and scale up the times as you choose. So, for Wh, kWh, MWh, etc - it's each of the activities below, for one hour


2 W average power used in charging a mobile (cell) phone

20 W laptop power consumption, at low processing levels

200 W food energy used by an adult at moderate activity levels (80 W sleeping, 1000 W sprinting)


2 kW (2000 W) a typical household kettle

20-25 kW a VW Golf or Toyota Prius travelling at 25mps (55mph)

200-300 kW fuel consumption of a sports cruising boat, 8m x 3m, travelling at 9m/s (18 knots)


2 MW (2000 kW) mean output of a typical new offshore wind turbine (5MW rated capacity at a mean 40% capacity factor)

20 MW Total electricity consumption by cloud storage provider Rackspace for all its datacenters which hold around 80,000 servers between them

254 MW peak output of the world's largest (as of 2013) tidal power station, Sihwa Lake, South Korea


1 GW (1000 MW) peak power output at the Alta onshore Wind Energy Center, US

22.5 GW peak output of the world's largest power station, the Three Gorges hydro-electric dam.

184 GW UK final energy demand (the UK ~ 60 million people, post-industrial G7 country)


1.5 TW (1500 GW) mean global renewable consumption (all uses, not just electricity). 2 TW global electricity consumption (from all sources, not just renewables); and also the potential mean generation of offshore wind in UK waters

17 TW global energy consumption, 2012

500 TW peak power of the world's most powerful laser (as of 2013)


1 PW (1000 TW) power in the sunlight falling on the USA

84 PW power in the sunlight falling on the Earth's surface

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Great! Maybe we can extend that list in the near future. –  junior Aug 19 '13 at 7:51
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Look up your television model, find the spec for power consumption (in watts), multiply by 1 hour. Google is very good for simple unit conversions and calculations like this.

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