Imagine that electricity could only be produced by burning wood. Let's assume we have just enough wood to produce the amount of electricity necessary to power a tablet for one hour. How many sheets of paper could be made from this wood instead of burning it? The heating value of wood is 13 MJ·kg⁻¹. During production, distribution and storage of electricity, 80% of the energy (heat) is lost. The tablet is fueled by a 3.6 V battery with current consumption of 0.5 A. One sheet of paper weighs 5.0 g and double of this mass in wood is needed for its production.