Energy: Units of Energy in our Everyday Life
In this blog post, I'll try to visualize how much energy we handle in our everyday lives. It's not rocket science but it's important to be able to relate quantities of energy to ones everyday life. The SI unit for energy is 1 Joule. Lifting an apple of 100 grams one meter corresponds to one Joule. One kilowatt hour corresponds to 3,6 megajoules. Like a 1 kW heater running for one hour. Comparing One Day of Manual Work with Buying Energy An adult of good fitness can sustain some 50-150 watts when biking one hour. 100 watts for one hour corresponds to 0,1 kWh. The efficiency of human muscles is some 20% , so the input energy of 0,5 kWh will give an output mechanical energy/work of 0,1 kWh. Eight hours of manual work consumes four kWh of input and generate 0,8 kWh of mechanical work. If one would instead choose to work at an office for 8 hours, that person would be able to earn some 1300 SEK after taxes (140 USD or 130 EUR). That money will buy almost 83 liters of di