Today, many homes – particularly those in areas where power supply can be unreliable – have a back-up generator. It’s a useful way to make sure that your home is supplied with electricity so you can continue to go about your normal routine in the event of a blackout. However, while having a generator in your home is a luxury, some workplaces absolutely need generator back-up power as a necessity.

related: Generator hire

Indeed, generators can be crucial emergency power systems in commercial ventures and public institutions where it can be seriously damaging to society and or commerce if they should close. Here’s a quick run down of the places in which you can expect to find emergency generators.

Power grids, hospitals and schools

Power grids often need emergency generators in place in order to continue the supply of electricity to businesses and homes in the event of power failure. This may be due to a fault at a power plant, but may also be caused by a widespread natural disaster, such as an earthquake or hurricane. In Japan for instance, the Tokyo Electric Power Company Incorporated (TEPCO) had to act quickly after the 2010 earthquake and tsunami struck, hiring generators to provide emergency power supply for parts of the country that had been left without electricity.

Hospitals and schools may also require emergency power from a generator. During World War Two, many makeshift hospitals were powered by crude generators as doctors and nurses needed at least minimal light to carry out their work. And in developing nations where the electricity supply can be unreliable and interrupted for several hours at a time, large schools that can afford it often have emergency generators on hand in order to maintain comfortable conditions for their students. Even those that don’t own a generator often consider hiring one if there is likely to be a period of regular power cuts on the horizon.