An integer for the number of timesteps per hour at which the energy balance calculation will be run. This has a dramatic impact on the speed of the simulation and the accuracy of results. Higher timesteps lead to longer simulations and more accurate results. At the lowest aceptable timestep of 1, the results can have an error up to 5% but increasing the timestep to 4 should drop errors to below 1%. (Default: 1). The following values are acceptable: (1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60)