AUSTIN, TEXAS — Energy efficiency measures or economic activities that aim to reduce the amount of energy required to provide the same amount of benefit or service will play an important role in the generation mix even as their present share remains minimal.

鈥淥ne of the areas we鈥檝e been really engaged in a number of countries in Asia, including the Philippines and Vietnam, is on air-conditioning efficiency because that is such a huge power need in demand as development continues,鈥 Kent D. Logsdon, principal deputy assistant secretary of the US State department鈥檚 Bureau of Energy Resources.

鈥淢ore and more people are looking for air-conditioners and obviously if you have air-conditioning that is not of the highest technologies then you鈥檙e gonna have a lot of loss and a lot of waste,鈥 he added.

He said in Europe, studies show the demand for energy fluctuates for development reasons but also sometimes because energy efficiency initiatives.

鈥淭here is a certain trajectory as you look over time that there will be less consumption in developing countries and developed countries as well because we鈥檙e more efficient,鈥 he said. 鈥淭he efficiency means you require less energy and you require less, in a way, of fossil fuels or renewables or whatever the source it鈥檚 gonna go down as efficiency goes up.鈥

These activities that results in the production of more output from the same amount of energy will only get better over time, said Becky Klein, principal of Austin-based energy consulting firm Klein Energy, LLC.

鈥淲e don鈥檛 count that into the mix. It鈥檚 just too small,鈥 she said.

But she said new technologies are coming into the market that are helping boost energy efficiency.

鈥淸These technologies are] what you see already on your phone being able to control your temperature remotely and turning off your lights remotely,鈥 she said.

Ms. Klein said artificial intelligence and machine-learning technologies are also coming into play to help utilities in predicting electricity usage.

鈥淸They] tell you in advance when to unplug things in your home, when to turn your temperature up, and I think that鈥檚 gonna become more and more significant over time,鈥 she said.

Based on statistics from the US Energy Information Administration, the United States uses and produces different types and sources of energy, which can be grouped into general categories such as primary and secondary, renewable and nonrenewable, and fossil fuels.

Primary energy sources include fossil fuels such as petroleum, natural gas, and coal; nuclear energy; and renewable sources of energy. Electricity is a secondary energy source that is generated from primary energy sources.

In 2018, the primary energy consumption in the US by energy source shows petroleum accounted for 36%, followed by natural gas at 31%, and coal at 13%. Nuclear energy made up 8%, or lower than the 11% usage for renewable energy.

鈥淚 think coal will continue to decrease, and nuclear will maybe go down a little,鈥 said Russel Gold, University of Texas journalism fellow and book author.

He said the decline in the share of coal would be picked up by gas and renewables.

鈥淲e鈥檙e quickly heading towards basically a gas and renewable market in the United States,鈥 he said. — Victor V. Saulon