completion of the first reactor on site. The hypothesised flexibility and modularity of SMR allows additional power generation capability to be installed at existing power plants. Modularity of a SMR plant allows for “a single site can have three or four SMRs, allowing one to go off-line for refueling while the other reactors stay online”. The flexibility of SMRs provides additional opportunities for industrial usage through saving energy lost through the transfer of energy from thermal to electrical. Applications for a SMR under these conditions of direct energy transfer include “desalination, industrial processes, hydrogen production, oil shale recovery, and district heating” of which a conventional large reactor is not capable. Economics A key driver of interest in SMRs is the claimed economies of scale in production, due to volume manufacture in an offsite factory. Some studies instead find the capital cost of SMRs to be equivalent to larger reactors. Substantial capital is needed to construct the factory - ameliorating that cost requires significant volume, estimated to be 40–70 units. According to a 2014 study of electricity production in decentralized microgrids, the total cost of using SMRs for electricity generation would be significantly lower compared to the total cost of offshore wind, solar thermal, biomass, and solar photovoltaic electricity generation plants. Construction costs per SMR reactor were claimed in 2016 to be less than that for a conventional nuclear plant, while exploitation costs may be higher for SMRs due to low scale economics and the higher number of reactors. SMR staff operating costs per unit output can be as much as 190% higher than the fixed operating cost of fewer large reactors. Modular building is a very complex process and there is "extremely limited information about SMR modules transportation", according to a 2019 report. A production cost calculation done by the German Federal Office for the Safety of Nuclear Waste Management (BASE), taking into account economies of scale and learning effects from the nuclear industry, suggests that an average of 3,000 SMR would have to be produced before SMR production would be worthwhile. This is because the construction costs of SMRs are relatively higher than those of large nuclear power plants due to the low electrical output. In 2017, an Energy Innovation Reform Project study of eight companies looked at reactor designs with capacity between 47.5 MWe and 1,648 MWe. The study reported average capital cost of $3,782/kW, average operating cost