Lewis Strauss coined in reference to the prospect of fusion power, the phrase too cheap to meter. Mr. Strauss argued that once fusion power would become available, the costs to produce electricity would be so low, that wouldn’t be worthwhile to charge the consumer in respect to their actual energy consumption.
The principal source of energy in Space Settlements is, of course, solar power. Our natural fusion reactor produces such amounts of power, that only a tiny fraction is needed for use by Space Settlers. Hence the question arises whether Space Settlers should be charged for their actual energy consumption?
Though the Sun does deliver its energy for free, it does not mean that the energy consumed by Space Settlers should be free. In order to make use of Solar energy, Space Settlers should convert it into useful forms of energy, such as electricity. This requires the construction of Solar Power Plants (SPPs).
And though a SPP has no fuel costs, it needs money for its construction and maintenance. Further the SPP has to be protected against meteorites and terrorists. It is obvious to someone has to pay for these services. And then we are only talking about the power plants, what to think about the construction and maintenance of the grid? But the good news is that even if we take these cost into consideration, space settlers will receive a considerably lesser energy bill than their terrestrial fellows.
The backside of SPPs is that the initial investment to build them, is quite high (though this would be compensated by the extreme long service life of the plants) and hence vulnerable to emerge of monopolists. After all once a space energy company has built a SPP, it can offer energy at relatively low prices, while the threshold of building a new plant will deter potential competitors.
Since such a monopoly is likely inevitable, it would be best if the governments of space settlements will take care of the production and maintenance of SPPs. This had two benefits: first all profits will flow to public treasury, and secondly price setting by the energy company is subject to democratic supervision.