In June 1940 two thirds of the employees were evacuated to England, leaving 36 volunteer employees to suffer the German occupation. Restrictions were placed on electricity usage, sufficient oil was available to provide reduced power until May 1941. The generation of power from burning waste was tested, with coal burning as a backup system, it helped meet the minimum essential load requirement of 145 kW. Supply fell to 3.4m kW, the main user of power was the German occupiers with most of their power being paid for by the States of Guernsey. Limited supplies of oil arrived on the island and generators were changed to run off town gas. The Organisation Todt (OT) who were constructing defences in the island were required to arrange for the delivery of oil to generate the electricity they needed.