spend the vast majority of our time—maybe 90% or more, by some statistics—inside buildings. And we spend a lot of that time uncomfortable.
There's more than just anecdotal evidence, though most
people have experienced overly-aggressive air conditioning in August, or
sweltering spaces in January. A new study from researchers at the Rochester
Institute of Technology finds commercial buildings are spending $600 million
more than necessary every year to heat and cool spaces, while wasting
significant energy doing so.
Eric Williams, an associate professor at the Rochester
Institute of Technology, was an author on the recently-published
"Co-alignment of comfort and energy saving objectives for U.S. office
buildings and restaurants," published in Sustainable Cities and Society.
"We’ve all had the experience of being or cold or hot
when we shouldn’t be," Williams said. But what seems like a fairly minor
irritation "is actually pretty darn significant. I was surprised."
And those findings are echoed by the focus of demand
management providers targeting these spaces for load control as well as
improved customer service. According to Neel Gulhar, senior director of product
marketing at Oracle Utilities, "nearly one in two of the buildings we’ve
looked at has an efficiency opportunity, and many of those are related to
heating and cooling."
According to Williams, who worked with RIT PhD candidate
Lourdes Gutierrez on the research, more than 40% workers are dissatisfied with
temperatures in their offices and almost 15% are very dissatisfied. That means
commercial spaces may be working hard to make more than half of their occupants
uncomfortable.
Much analysis has been done in the residential space, and
manufacturers have created lines of intelligent devices aimed at keeping the
home comfortable while saving energy. But the math is simpler—an apartment or
single-family home has far fewer people to satisfy, and temperature is more
likely to align with comfort. But as buildings grow in scale and capacity, the
same decisions are increasingly complex and impact more employees and
customers, as well as profits.
Changes for comfort, climate
In terms of real energy consumption, Williams and Gutierrez'
research is ... chilling.
Changing office building temperatures to better match
employee comfort could save 3,100 GWh in electricity and 17,500 billion Btu in
natural gas each year—about 1.4% of total office building power consumption and
6.5% of gas burn. Similar changes in full-service restaurants could achieve
savings of 1,300 GWh in electricity and 2,800 billion Btu in natural gas, or
about 2% and 1.4% savings, respectively.
In total, the analysis shows primary energy savings of
almost 70 million gigajoules of energy—2.5% of the energy used in office
buildings and restaurants, leading to annual savings of $600 million
If you add in hotels, stores and other types of commercial
structures, Williams said simply revising thermostat settings could drop
national carbon emissions by 0.3%—about the equivalent of pulling 4 million
cars off the roads, he said. For reference, Williams noted annual potential
savings from thermostat settings is comparable to the total energy generation
by U.S. solar PV generation in 2015, almost 84 million GJ.
And all we have to do to recapture some of it, he said, is
"get people to change their thermostat in an intelligent way,"
ultimately getting "more people to share the burden."
"Our results create a motivation for increased
government activities to understand thermostat settings and comfort because
their energy implications relate to a public good, climate, rather than simply
being a private sector affair," the paper concludes.
It is not quite as simple as making everyone more
comfortable, however. Different organizations are driven by competing
factors—some prizing operations over efficiency, or simplicity ahead of
efficacy. "It is not currently clear how different organizations think
about and implements thermostat settings," the report found, adding,
"it is important that more information be collected on this issue."
For instance, better-aligned thermostat savings in the
restaurant industry will save your average establishment more than $500,
Williams said.
"But thermostat settings must, however, compete for a
restaurant manager’s attention among many other issues," the report
explained. "It is not clear that if $510 savings is sufficient."
Finding a comfortable solution
Restaurants operate on paper-thin margins, and national
climate goals make carbon emissions an issue for all organizations. But if the
savings are modest an each facility, how do you get building managers to
effectively make changes?
And isn't this exactly the issue that learning thermostats,
smart buildings and demand management systems were designed to tackle?
In larger commercial buildings the heating and cooling is
often controlled by a building management system, said Orace's Gulhar.
"While these systems are inherently 'smart' – they can be programmed and
adjusted – they need to be commissioned to heat and cool to the right
temperatures at the right time of day," he said.
Gulhar and Indran Ratnathicam, vice president of marketing
and strategy at First Fuel, a strategic partner of Oracle's, answered some
questions on commercial building optimization via email. In many buildings,
they explained, the commissioning isn’t regularly monitored, resulting in
issues with both temperature and efficiency.
Oracle, which recently scooped up cloud-based demand
management provider Opower in a $500 million deal, has learned from its work in
the residential space, where smart thermostats are helping maintain efficiency
and comfort. "We’ve found a similar opportunity in the small business
space," the two executives said. "Small business owners and operators
want to focus on running their business, and don’t want to worry about setting
their systems exactly right for comfort and cost. ... Smart/learning
thermostats could have a big impact for this segment."
Utilities can play a big role in optimizing smart
thermostats, and some have already seized opportunities to do so. For example,
the recent partnership between Nest and Southern California Edison to build a
virtual power plant to mitigate potential fuel shortages from the Aliso Canyon
methane leak. Another example is ComEd's initiative to install 1 million smart
thermostats in its Chicago-area territory by 2020.
Not to mention thermal storage. Ice Energy's Ice Bear unit
aims to help building managers manage air-conditioning units, and can be owned
or operated by the utility.
More data, better defaults are needed...
But only if people better understand the problem, possible
solutions, and the potential savings.
There are a couple of solutions identified in Williams and
Gutierrez' paper. First are broader temperature settings, adjusted for climate
zones, in building management systems. Better accounting for the clothes people
actually wear, in different regions of the country, can also make a significant
dent.
But the federal government can take steps to better define
the issue, they said, and possibly put that data in the hands of building
managers. "If you have a smart thermostat, you'll know what's going on in
your building," Williams said. "But unless there is some integrated
effort to bring that to a clearing house, that information will stay isolated."
Williams said thermostat vendors, or building management
software developers, could consider a repository for initial temperature
settlings. And the U.S. Energy Information Administration can begin collecting
data on thermostat settings in commercial buildings—something it already does
on the residential side.
EIA's Commercial Buildings Energy Consumption Survey tracks
statistical information on energy-related characteristics, consumption, and
expenditures for the nation's 5.6 million commercial buildings, but it doesn't
include questions on thermostat settings. EIA's Residential Energy Consumption
Survey, however, does as thermostat setting questions, so Williams' paper
posits that "extending to CBECS should be straightforward."
"You still have to figure out where to set the
thermostat," Williams said, and "it’s not clear how those building
managers are making that decision. But depending on where you live and what
season it is, you can make people more comfortable and save energy."
FirstFuel's Ratnathicam said his company analyzes data for
millions of buildings for utility partners, often revealing lapses.
"In an ideal world, when a building is first built, the
heating and cooling settings would be commissioned to optimal efficiency
levels. But, there are many buildings that have never been commissioned or
older buildings where settings have not been monitored or adjusted in a number
of years," Ratnathicam said. He said FirstFuel's platform can optimize
heating and cooling inefficiencies, examine occupancy schedules and identify
issues like simultaneous heating and cooling – where both systems in effect
cancel each other out.
A building manager is just trying to do the right thing for
occupants, often meaning daily adjustments to temperature settings. "But
after 6, 12, or 18 months of corrections, the altered settings leave many
people uncomfortable and the whole building inefficient," Ratnathicam
said.
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