London wants to make the city's 2012 Olympic Games the greenest games ever – and that effort could be an entryway for investors and companies looking to help the city on its estimated £20 billion ($32.6 billion) effort to cut greenhouse-gas emissions by 60 percent by 2025.

That's the news from a Wednesday event in San Francisco to promote London's green Olympic goals. Hosted by the promotional group Think London, it provided guides for getting involved, both in the games' sustainability efforts and the longer-term goals of making London a "green capital" of the world, said Padmesh Shukla, head of finance for London's Climate Change Program. He said the city's greenhouse-gas reduction goals would require massive investments over the coming decades, with a focus in four key areas.

First, London wants to retrofit more than 26 million square feet of government and commercial real estate for energy efficiency, he said – a natural opportunity for large-scale energy services companies (ESCOs) like Honeywell or Siemens, but also potential grounds for innovative new businesses (see A PPA Model for Building Energy Efficiency?).

The city also wants to boost its hybrid bus fleet and build the charging infrastructure to get 100,000 electric vehicles on city streets by 2020, he said. London has been talking to Palo Alto, Calif.-based battery swapping and recharge startup Better Place about that, but is also working with other companies, with an eye toward getting 25,000 charging points in the city by 2015, he said (see Toyota's Plug-In Prius Heads for France).

London also wants to draw major investments into recycling industrial waste, he said. Finally, it's seeking big investments into decentralized power plants, including a big push into combined heat and power systems, to provide a quarter of the city's power supply by 2025.

"The key thing is to find [private] money" to finance those ambitious goals, Shukla said. To help get there, the city is proposing a "London Green Fund," seeking to raise about £150 million ($245 million) in public funds to kick start private investment in those four categories, he said.

That could help finance projects to prove their viability to banks and other investors that are loath to invest in unproven technologies, he said.

"This is a really tough market to be raising money," Shukla said. "We're pretty clear that the initial set of funding has to come from us."

As for the games themselves, they include a huge urban renovation project at the heart of the £9.3 billion ($12.2 billion) Olympic Park that includes a host of sustainability features, said Dan Epstein of the Olympic Delivery Authority, the public agency in charge of building it.

That includes an Olympic Stadium that can be downsized from an 80,000-seat to a 25,000-seat facility once the games are over, allowing the reuse of building materials, he said.

It also includes an energy center that includes biomass boilers and a combined cooling, heat and power plant that will continue to provide power at a 30-percent discount to grid power for decades after the games are over, he said.

As far as business opportunities for supplying the games, Epstein said his group was searching for "smart waste technology," and small-scalesolarpower or other renewable power resources.

Then there are sustainability standards for companies that want to provide goods and services for the games itself, which include rules for sourcing sustainable products made from recycled materials with a minimal amount of embodied energy in them, said Janet Coyle, Think London's 2012 Games director.