According to research from Bloomberg New Energy Finance, worldwide investment in clean energy dropped to its lowest level in four years during the first three months of this year.  Total investment, which includes renewables, energy efficiency, and energy-smart technologies, was down 38% from the last quarter of 2012 and 22% from the same period (first quarter) of 2012.  The causes identified by BNEF include policy uncertainty in major markets like the U.S. and Germany and the sharp decrease in prices of solar PV panels which translates to lower investment, in dollar terms, for a project of equal capacity.

The year-on-year decline was sharpest in the U.S., with less than half the amount invested in the first quarter of 2013 as was invested in the first quarter of 2012.  A large part of this was the potential expiration of the Production Tax Credit ("PTC") at the end of 2012, which motivated many wind project owners to accelerate their development schedules.  This essentially shifted investment from 2013 into 2012 and even 2011.  Congress ultimately renewed the PTC in January.

Investment also dropped in Europe (25%) and China (15%) but jumped by 47% in the rest of Asia (excluding China and Asia), led by Japan.

By type of investment, the biggest decline was in the asset finance of utility-scale projects, which fell by 34%.  Investment in small (< 1MW) installations - primarily rooftop PV - also dropped 8%, due mostly to the lower cost of PV panels.

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