Global energy investment in 2015 amounted to $1.8 trillion, down eight percent from 2014 mainly due to a sharp fall in upstream oil and gas investment, according to the International Energy Agency’s (IEA) World Energy Investment 2016 report, published on its official website, according to Trend News.

Renewable energy investments of $313 billion accounted for nearly a fifth of total energy spending last year, establishing renewables as the largest source of power investment, according to the report.

“While spending on renewable power capacity was flat between 2011 and 2015, electricity generation from the new capacity rose by one third, reflecting the steep cost declines in wind turbines and solar PV. The investment in renewable power capacity in 2015 generates more than enough to cover global electricity demand growth,” the report said.

Fossil fuels continue to dominate energy supply, but the composition of investment flows points towards a reorientation of the energy system, the IEA report said.

The agency also noted that with energy supply spending of $315 billion, China was once again the world’s largest energy investor last year thanks to robust efforts in building up low-carbon generation and electricity networks, as well as implementing energy efficiency policies.

Last year, upstream oil investment remained robust in Russia and the Middle East, helping to push up the share of national oil companies in oil and gas upstream investment to an all-time high of 44 percent, according to the IEA’s report.

The impact of low oil prices on cash flow tested the debt-financed investment model of the US shale oil industry, leading to a particularly sharp fall in investment of 52 percent in that sector in the past two years, the IEA said.

The report said that investment in the US energy supply declined to about $280 billion in 2015, falling nearly $75 billion, due to low oil prices and cost deflation, representing half of the total decline in global energy spending.