Governments and the private sector spent about USD 359 billion (263 billion euros) in 2012 -- down from USD 364 billion the year before, said a report by the Climate Policy Initiative (CPI), an independent team of climate finance analysts and advisors.
The analysis was unveiled at a meeting of the Global Green Growth Forum which includes representatives of governments, the business sector, investors and international organisations working for cleaner, safer energy.
This goal is mainly being targeted by projects to reduce emissions of Earth-warming carbon dioxide (CO2) created through fossil-fuel burning for energy production and transport.
The World Bank has since projected a temperature rise of 4.0 C by the end of the century -- triggering more extreme heat waves, declining global food stocks and sea-level rises affecting hundreds of millions of people.
"Efforts to scale up finance are falling further and further behind," said a CPI statement.
"While public support for climate activities was significant, it was still dwarfed by current government support to fossil fuel energy consumption and production," said the statement.
"Private investors, who can and should provide the lion's share of global climate finance for good reason -- as asset owners and end users of renewable technologies -- only invest their money when the returns on offer outweigh the costs," added the CPI.
Developed countries spent about USD 177 billion and developing states USD 182 billion on climate investment, said the CPI.
Technological progress meant there was "some cause for optimism" in renewable energy, it noted.
