We propose the introduction of an energy-based parallel currency as a means to ease the transition to energy-conscious living. Abundant fossil energy resources mask the internal and external energy costs for casual energy consumers. This situation is challenging communities that draw a significant fraction of their primary energy consumption from renewable energy sources. The Masdar Energy Credit (MEC) system is a way of translating the fundamental aspects behind energy generation and usage into a tangible reality for all users with built-in fungibility to incentivize collectively sustainable behavior. The energy credit currency (ergo) corresponds with a chosen unit of energy so that the total amount of ergos issued equals the energy supply of the community. Ergos are distributed to users (residents, commercial entities, employees, and visitors) on a subscription basis and can be surrendered in exchange for the energy content of a service. A spot market pricing mechanism is introduced to relate ergos to "fiat" currency using a continuously variable exchange rate to prevent depletion of the sustainable energy resource. The MEC system is intended to: (i) meet the sustainable energy balance targets of a community (ii) support peak shaving or load shifting goals, and (iii) raise energy awareness. (C) 2009 Elsevier Ltd. All rights reserved.