The report says that 1.8T kWh, or 54%, of the increase in annual output of renewables is forecast to be met by hydro power by the end of the 2006-2030 period.
It added that apart from wind power - estimated to meet a third of the renewables supply - most other technologies were believed not to be economically competitive with fossil fuels over the 24-year period.
In total, total renewables output (non-OECD and OECD) is projected to increase from 3.2T kWh in 2006 to 6.7T kWh by 2030.
Annually, hydro power generation globally is forecast to rise in OECD countries from 1.3T kWh in 2006 to 1.5T kWh by 2030.
In non-OECD countries, the increase in hydro output is projected to increase from 1.7T kWh/yr in 2006 to 2.5T kWh/yr in 2015 to 3.2T kWh/yr by 2030.
The main area for growth in hydro power projects will be non-OECD countries with mid- to large-scale scheme in China, India, Brazil and parts of Southeast Asia. Few large-scale hydro projects are planned for OECD countries.
While wind is also seen to have significant growth potential in non-OECD countries, along with biomass it is also seen, however, to be the dominate area of renewable energy growth in OECD countries.
Global electricity generation is forecast to jump by about three-quarters to almost 32T kWh by 2030 compared to output in 2006. The study assumes that growth will get back to trend after next year following the impact of the current economic recession.
Despite increasing efforts to promote carbon offsetting projects, including hydro power schemes that may also benefit economically from carbon credit revenues, the report noted that coal consumption was projected to increase at 1.7% on an average annual basis to 2030.
With respect to non-OECD Asia, the report added: 'In fact, much of the region's increase in energy demand is expected to be met by coal, particularly in the electric power and industrial sectors.'
