Recent decreases in the installed costs of residential and non-
residential solar photovoltaics (PV) bode well for ECs, since
the decreases make the technology more attractive to more
customers. Each year, Lawrence Berkeley National Labora-
tory publishes the report “Tracking the Sun,” which identifies
trends in solar PV. In past years, the report has included resi-
dential, nonresidential and utility-scale PV trends. This year,
however, utility-scale PV trends were spun off into a sepa-
rate report, “Tracking the Sun VIII: The Installed Price of
Residential and Non-Residential Photovoltaic Systems in the
According to the report, the overarching trend is that
“installed prices” continue to decline rapidly. The national
median installed price in 2014 for residential systems declined
year-over-year by $0.40 per watt (a 9 percent decline). The
national median installed price for nonresidential systems
under 500 kilowatts (k W) declined year-over-year by $0.40
per watt (a 10 percent decline). The national median installed
price for nonresidential systems over 500 k W declined year-
over-year by $0.70 per watt (a 21 percent decline).
“Preliminary data for the first half of 2015 indicate that
installed price declines have persisted into 2015 and are on
pace to match those witnessed in recent years,” the report said.
The growth in large-scale batteries is expanding rapidly and the
most popular type is lithium-ion. The batteries store energy for
use when the generation capacity temporarily comes to a halt
(such as when the equipment breaks down or requires maintenance) or weakens (as can be the case with the instability of
solar and generation).
According to “State of the Electric Utility 2015,” published
by Utility Dive, U.S. energy storage capacity grew 40 percent
from 2013 to 2014 and is expected to grow almost another 300
percent from 2014 to 2015 to 220 MW. Lithium-ion batteries
represent about 70 percent of the storage market, with the
remaining 30 percent being composed of flywheels, flow batteries, and sodium chemistries.
Ravi Manghani, an energy storage analyst with GTM
Research, was quoted in the Utility Dive report: “Broadly speaking, we expect lithium ion to be the biggest battery technology
deployed through 2019,” he said.
According to “Batteries Charge Up For the Electric Grid,”
a September 2015 report by Moody’s Investors Services, many
lithium-ion battery-storage applications could become economically viable by the end of the decade, as long as prices
continue to fall. These applications include peak-shaving for
commercial and industrial customers, grid storage to integrate
renewables, and fast-response ancillary services. And, according to a recent GTM Research report, the solar-plus-storage
market is expected to reach $1 billion by 2018, and the U.S.
energy-storage market in total will reach $1.5 billion.
On the residential side, Tesla’s Powerwall battery, introduced in early 2015, will likely change how homeowners
view electric power. The new line of stationary, rechargeable
lithium-ion batteries for homes and small commercial buildings
is designed to store energy so that it can be used when energy
is unavailable (during a grid power outage) or less expensive
(with solar-panel-storage applications).
The moderately priced Powerwall units do not include
installation or the required DC-AC inverter. Tesla plans to create a network of certified installers.
DER on the commercial side
Commercial, governmental and retail customers are quickly
embracing DER. In 2015, for example, Walmart broke ground
on its 300th solar-power project, expanding its PV output to
100 MW across 14 states.
“What we have found over time is that, once we’re successful
with on-site solar at one location or state, opportunities begin
to open up in other states,” said David Ozment, senior director
of energy, Walmart. “We literally work across the United States
to try to make solar work in that particular capacity.”
DER on the residential side
According to the California Public Utilities Commission
(CPUC), zero-net-energy (ZNE) homes, which would focus
resources on the Way?