Tokyo is helping energy companies to reduce CO2 emissions and shift to renewable energy by requiring them to regularly publish the amount of carbon dioxide they are emitting, and demonstrate their plans to shift to renewable supplies. In the first year of operation, six out of nine electricity companies had reduced their emissions by a total of 680,000 tons CO2. The strategy is simple - by requiring energy companies to show customers their green credentials, the City is driving greater competition for renewable-sourced energy. The City wants 20% of all energy to be renewable by 2020.

What is it?

A program to shift energy companies from fossil fuel use to a higher use of renewable energy.

How does it work?

Under the program Tokyo Electric Power and other power producer and suppliers (PPSs), are required to release plans and reports including:

  • the CO2 emission factors (CO2 emission factor: Greenhouse gas emission per electricity kilowatt hour)
  • the reduction target for the factor
  • the actual introduction of renewable energy
  • future schedules for the introduction of renewable energy

The environment-consciousness of these electricity companies is then officially announced through the release of these plans and reports. Importantly, this helps electricity customers choose the most environment-conscious companies, driving competition for renewably sourced energy.

Companies that do not and announce the findings of their reports are then formally asked to do so by the Tokyo Metropolitan Government (TMG). If the company still does not submit details, then the Government announces its name to the public, as a non-participant.

Electricity companies are reducing their CO2 emission factors in two ways:

Internal efficiencies

  • improving their existing power generation units; and
  • switching to cleaner fuels.(From coal and oil to natural gas)

Supply efficiencies

  • generating and purchasing more renewable energy, such as biomass, hydraulic power and wind power;
  • each company has different plans to increase renewable energy and renewable resources.

Tokyo Renewable Energy Strategy

TMG has also developed the Tokyo Renewable Energy Strategy - which sets a strong target of 20% renewable energy supply by 2020 for the city. The Strategy also includes a new framework setting out the rules that govern renewable energy use in large-scale facilities.

CO2 emissions

The program is already cutting emissions by 680,000 tons CO2 annually. (This is about a 1% reduction of total CO2 emissions in Tokyo – based on the same electricity consumption in 2005 as 2004 (84.9 billion kWh).


The electricity market in Japan was partly liberalized in April 2005, since then all consumers who are provided high-tension power are able to choose the electricity company.

Any city, which has liberalized electricity markets, can replicate this program and stimulate consumers to choose cleaner energy by showing them the data of quality of electricity.