The most successful cities in the world at building sustainable urban environments have been recognised at the UN climate talks in Warsaw.

The cities are winners of the World Green Building Council's (WorldGBC's) Government Leadership Awards, a biennial competition held in partnership with ICLEI and UN-HABITAT. These highlight policies and practices that maximise the opportunities for buildings to mitigate environmental impact.

The theme this year, the second time the awards have been made, is Global Excellence in Local Green Building Policy.

Vancouver, Canada, is the overall winner in the category 'Best Green Building Policy', for its Greenest City 2020 Action Plan. The award recognizes the City's leadership on green buildings, and its ambitious targets for all new buildings constructed from 2020 onward to be carbon neutral and to reduce energy use and greenhouse gas emissions in existing buildings by 20 per cent over 2007 levels by 2020.

Abu Dhabi, United Arab Emirates received the 'Regional Leadership Award' for the Estidama Pearl Rating System – a program that has efficiently and effectively implemented mandatory sustainability requirements in the Emirate's development sector, where previously there were none.

Christchurch, New Zealand, was presented with the 'Urban Regeneration Award' for its policies and initiatives aimed at sustainably rebuilding itself after a series of devastating earthquakes.

One Less Nuclear Power Plant from CONEW on Vimeo.

Seoul, Korea, was honoured with a 'Climate Action Leadership Award' for its One Less Nuclear Power Plant initiative, a three-year initiative that aims to reduce energy consumption in the city.

Also receiving honourable mentions are:

• Brighton and Hove, United Kingdom, for its Food Growing and Development Planning Advice Note; 
• Cape Town, South Africa, for its Municipal Energy Efficiency Buildings Program;
• Shanghai, China, for its Green Building and Eco-City Campaign.

"These awards not only recognize the commendable efforts of local governments to transform their buildings, their communities and their cities," said Jane Henley, Chief Executive Officer of the World Green Building Council.

"They also acknowledge our challenge to implement sustainability measures on a city-wide scale in our increasingly urbanized world. The efforts of all of our nominees are proving that building industry solutions not only reduce emissions, but also make economic sense."

The winning cities were chosen by representatives from UN-HABITAT, ICLEI and the WorldGBC. The winners were announced at the Warsaw Dialogue on Scaling-Up Local and Subnational Climate Action, held in conjunction with the UN Climate Change talks, COP19.

Vancouver's Greenest City 2020 Action Plan

The city aims to become the greenest city in the world and is working with council residents, businesses and other organisations plus all levels of government to implement its program. Its action plan is divided into 10 goal areas with a specific 2020 target for each one, grouped under the headings of carbon, waste and ecosystems.

The latest development in its program is to mandate that from March 20, 2014, new one- and two-family homes will need to meet increased energy-efficiency requirements utilising improved insulation, air-tightness and high efficiency heating systems. In addition, buildings under renovation will need energy audits and minor upgrades.

The city is also constructing a 28km Seaside Greenway and a new York Bikeway from Stephens Street to Seaforth Park as part of its Greenest City Action Plan and Transportation 2040 Plan supporting walking and cycling in the city.

Abu Dhabi's Estidama Pearl Rating System

The city's program, launched in 2010, has rating systems for the community, building and villa level. At the community level the conservation of water, energy and waste is encouraged together with the use of local materials and the improvement of supply chains for sustainable and recycled materials and products.

All new community developments from 2010 had to meet the 1 Pearl requirements, specified in building codes. Water, waste and energy use calculators were provided.

Cape Town's Energy Efficiency Program

The city's efforts to reduce energy consumption include a Municipal Energy Efficiency Demand Side Management (EEDSM) program, funded by grants which support eco-retrofits within the municipal infrastructure. It has improved its street lighting, traffic lighting and municipal buildings.

"Implementing the first (and to date, the only) guaranteed savings contract within a municipal framework in South Africa required innovation on a number of levels," said Councillor Garreth Bloor, the City's Mayoral Committee Member for Economic, Environmental and Spatial Planning.

"It has proven to be a highly effective model. The success of this programme has provided the foundation for the development of the City of Cape Town's Internal Energy Management Policy which requires energy efficiency programmes across all departments."