Dive Brief:

• The cost to construct new electricity capacity has been broadly declining, according to an analysis of data from 2013 to 2015, conducted by the U.S. Energy Information Administration.
• Wind, gas and solar dominated new capacity additions in 2015, adding 8.1 GW, 6.5 GW, and 3.2 GW, respectively. While all three resource types saw declining construction costs, the decline was most dramatic for natural gas plants.
• EIA data shows the cost of utility-scale solar resources declined 21% between 2013 and 2015, from $3,705/kW to $2,921/kW. Combined-cycle gas generators had an average installed cost of $614/kW in 2015.

Dive Insight:

The declining cost of renewable resources has been touted for some time now, but EIA's analysis illustrates that it isn't just carbon-free generators benefiting from the trend. Natural gas plants saw the steepest decline in construction costs, in part due to the growth of highly-efficient combined cycle plants.

Overall, EIA said the average cost of natural gas generators installed in 2015 was $696/kW— a 28% decline from 2013. Almost three-quarters of added capacity that year was combined-cycle units, which had an average installed cost of $614/kW.

The agency said about 1.5 GW of natural gas plants with only combustion turbines were installed in 2015 at an average cost of $779/kW.

While wind and solar also saw double-digit declines, they were not quite as steep. The cost of utility-scale solar declined 21% between 2013 and 2015, from $3,705/kW to $2,921/kW or nearly $3/watt. An earlier report from the Solar Energy Industries Association and GTM Research noted fixed-tilt utility-scale solar systems priced at an average of $0.99 to $1.08/watt this year. 

 EIA said the capacity-weighted cost of installing wind turbines was $1,661/kW in 2015, a 12% decrease from 2013. EIA also said that 2015 was the first year it recorded construction costs of battery storage, which came in at $864/kW.