Heat intolerance is a major medical problem affecting people with multiple sclerosis (MS). When their core body temperatures increase people with MS experience significantly increased symptoms which greatly reduces their capacity to participate in social, household and work activities, as well as increasing their need for pharmaceuticals and medical services. For people with MS, using air condi-tioners is a medical necessity. This work was carried out in partnership between the University of South Australia and MS Australia to develop an accurate understanding of electricity consumption patterns in MS households, particu-larly in relation to their need to keep cool to avoid increasing their MS symptoms. This research involved surveys and examining energy bills in 38 households of people with MS. Participant households used, on average, about 16.8% more electricity in summer and 10.5% more electricity in winter than the average for the area. This increased to 32.2% more in summer when the 24% of homes with solar PV were removed. Examining non-solar homes more closely, summer electricity use showed those using more than the average (60% of sample) used about 80% more electricity while the rest used 18% less. The latter were predominantly found to have introduced energy savings initiatives and were careful about en-ergy use. The research provided evidence that people with MS require more air conditioning to keep cool as a result of their medical condition. The work provides vital material for future policy in relation to sup-porting vulnerable and often low income households with high energy use due to medical need.