“…Although human activities, including the burning of fossil fuels and deforestation, were only responsible for 3% of carbon dioxide (CO 2 ) emissions worldwide in the 1990s, the increase in emissions was large enough to exceed the absorptive capacity of natural processes (e.g., photosynthesis). Energy use for power generation in the industrial [2,3], residential [4,5] and transportation sectors [6,7] has been the largest contributor of GHG emissions. In particular, approximately 10-35% of national energy consumption was from the residential sector worldwide in the late 1990s and 2000s [8], and this figure will likely increase as the average person's income, standard of living, and associated access to home appliances, housing and personal transportation increase.…”