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Solar Power in the USA—Status

and Outlook

Michael Ginsberg, Vasilis M. Fthenakis
CENTER FOR LIFE CYCLE ANALYSIS, COLUMBIA UNIVERSITY, NEW YORK, NY, UNITED STATES
vmf5@columbia.edu

4.1 Overall US Market Indicators

Presently, solar energy remains a minority contributor to the United States (US) energy
production at 1.4% of the 2016 energy mix [1]. In recent years, the US energy market has
shifted from coal and nuclear energy to increased reliance on natural gas in the ß US and
solar and wind renewable energy in the Western US between 2009 and 2014. Natural gas
based power generation increased by 204.6 TW h, a 22% increase, and non-hydrorenewable
energy by 130.8 TWh, an 85 % increase (Table 4.1) [2].
US Energy Demand: US energy consumption in 2016 totaled 102.3 EJ (97.4 quadrillion
Btu), a slight increase from 2015 (Fig. 4.1). The 9% decrease in coal use was more than
offset by rising natural gas, petroleum, and renewable (mostly solar and wind) energy gen-
eration [3] (Fig. 4.2).
In the US, the world’s second largest energy producer and consumer, the demand for
electricity has historically been determined by heating, ventilation, and air conditioning
(HVAC) needs, or heating and cooling degree days, and the state of the economy, or Gross
Domestic Product (GDP).
The Decoupling of Economic Growth from Energy Use: The US National Oceanic and
Atmospheric Administration (NOAA) showed the total number of cooling degree days
(CDDs), which is tied to air conditioning and electricity usage, have increased over the
past 100 years. CDDs for the summer of 2016 surpassed the 2011 record [3].
Historically, US energy and electricity use has been tied to economic growth. Over
the past 25 years, however, GDP has risen by 80% while primary energy consumption
rose by only 14%. Over the past 10 years, GDP rose by 12%, and energy consumption fell
by 3.6%. This points to a new factor, energy efficiency, with some estimates that efficien-
cy gains account for 60% of the energy intensity improvements since 1980 (Fig. 4.3) [4].
Utility decoupling, the separation of utility revenues from the amount of electricity
generated and sold, has been key to this trend. In addition, energy efficiency regulations
have incentivized utilities to implement energy efficiency measures among customers. In
2015, electric utilities spent over $6 billion on efficiency programs and natural gas utilities

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