ARPA-E seeks to mitigate the greenhouse gas emissions associated with commercial air travel at minimum economic cost by developing elements of an ultra-high efficient aircraft propulsion system that uses Carbon Neutral Liquid Fuels (CNLFs). Since these fuels generally either have lower specific-energies (kWh/kg) or are projected to have higher cost than traditional fossil-based jet fuels, ultra-high conversion efficiency is critical for the economic viability of this approach. An electrified propulsion system framework postulated by ARPA-E could potentially leverage multiple sources of stored energy (e.g. CNLF, batteries, etc.) to facilitate emerging propulsion concepts (e.g. distributed propulsion) and enable net-zero carbon emissions for long range, narrow-body, commercial aircraft. The objective of the REEACH program is the development of one element of the electrified propulsion system framework: a system for the conversion of chemical energy contained in energy dense CNLFs to electric power for aircraft propulsion and hotel loads.