Act 234 calls for the state of Hawai‘i to return its greenhouse gas (GHG) emissions to 1990 levels by 2020. Under a business as usual environment, we forecast Hawai’i’s 2020 emissions to be between 18 and 34 percent above 1990 levels. Since transportation and electricity account for about 75 percent of Hawai’i’s GHG emissions, most likely a large share of the reductions will need to come from these sectors for Hawai’i’ to comply with Act 234.
