The government is looking at sweeping measures to reduce greenhouse gas emissions, by enhancing energy efficiency, capping energy consumption levels in buildings, and requiring building owners to prove their compliance with such levels when selling their properties. The ideas were presented in a report submitted to the Presidential Committee on Green Growth by the Ministry of Land, Transport and Maritime Affairs on Thursday.

The ministry's plans would require building owners to make their structures "zero energy" by 2025. So-called zero energy buildings use renewable energy sources such as solar power, wind power or geothermal heat to produce all the energy they need.

The plan would gradually reduce energy consumption levels for residential buildings, with a 30 percent cut by 2012, and a 60 percent cut by 2017.

From next year, building permits will be given for new buildings which meet certain gas emissions and energy consumption levels. The measures will be applied to existing buildings from 2011. And one million of 1.5 million houses being built for low-income families by 2018 will be energy-saving models.

The plan would also slash emissions in the transportation sector, which currently accounts for 17 percent of Korea's greenhouse gas emissions, by 30-37 percent by 2020. Starting next year, areas that are heavily congested or with excessive emissions would be monitored. Vehicles driving through these areas would have to pay congestion charges, while green transport such as electric cars would be given preference.