Navigant Research Blog

Air Conditioning Controls Overlook Comfort

— August 12, 2015

If you work in an office or know someone who does, you have probably already heard that the patriarchy has set the thermostat too low. A recent study by two Dutch researchers seemingly provided proof of this institutional sexism and promptly set off an Internet firestorm. The study claims that the model that ties thermal comfort to the air temperature used for the control of air conditioning systems relies only on data from men. Moreover, because the metabolic rate of males and females are different, the approach provides too much cooling for female occupants, leaving them to suffer in frigid conditions while their male counterparts are comfortable. The study is unfortunately wrong on two counts: air temperature settings are based on data from equal amounts of men and women, and both men and women suffer from temperatures that are too cold.

If You Can’t Measure It, You Can’t Manage It

Controls for air conditioning need to be set to something that can be measured. Thus, air temperature, which can be measured and is highly correlated to thermal comfort, is used to manage the operation of air conditioning equipment. The specific temperatures engineers use for systems are set by the American Society of Heating, Refrigerating, and Air-Conditioning Engineer’s (ASHRAE’s) Standard 55, Thermal Environmental Conditions for Human Occupancy. In a press release, ASHRAE reiterated the fact that Standard 55 is based on the preferred temperature of more than 1,000 subjects with an equal amount of men and women. Unlike paychecks, Standard 55 does not have a gender bias.

The problem highlighted by response to the Dutch study is that temperature and comfort are related but not identical. How comfortable a person feels in a building depends on how much cooling they need (what they are doing, what they are wearing, how old they are, and their body fat) and the state of the air that is provided (temperature, humidity, volume, and speed). Controlling a system that depends on a dozen variables by a single variable leads to both women and men being uncomfortable. Saying that the average person is comfortable at a certain temperature is akin to describing a person with a chicken and a person without a chicken as two people who have an average of half a chicken.

Utopia with the Dialogue of Comfort

Wouldn’t it be great if air conditioning was controlled by comfort rather than temperature? Historically, this dream has been technologically unfeasible. To truly measure comfort, the feelings of building occupants need to be gathered. Not only are engineers bad with feelings, but there isn’t a sensor that can measure them. Nonetheless, air conditioning systems are moving toward comfort-based control.

The Leadership in Energy & Environmental Design (LEED) building certification program, which rates buildings based on their indoor environment and ecological impact, credits building operators for assessing how comfortably occupants actually are through a survey. Building Robotics, an Oakland-based startup, closes the comfort control loop with its Comfy software. Rather than relying on exclusively on sensors, Comfy has occupants provide direct feedback via a web or smartphone app and changes temperature and airflow accordingly. As better technology enables better building controls, women and men alike will be able to find comfort in the built environment.


Emerging Technologies Address Water Management Dearth

— August 4, 2015

It’s been the kind of balmy summer in Washington, D.C. that makes Washingtonians thankful for air conditioning. Blasts of cool air offer a welcome greeting in homes, offices, and stores throughout the region. Unfortunately, the trek between those cool oases can be terrible, particularly when using public transportation. Though the stations, buses, and railcars of the Washington Metropolitan Area Transit Authority (WMATA) are equipped with air conditioning, maintaining an appropriate temperature has been a persistent problem.

In normal times, WMATA struggles to provide adequate air conditioning. In June, WMATA faced catastrophic failure in the chilled water plant that serves two stations (Dupont Circle and Farragut North). The chilled water plant in question consists of a chiller, a cooling tower, and air handling units to provide cool air in the stations. The chiller uses the refrigeration cycle to cool water that is distributed to the stations’ air handling unit and reject heat to the cooling tower. The cooling tower relies on evaporation to then reject heat to the atmosphere (the same principle that makes that bird go up and down). For WMATA, the water piping that connects the chiller to the cooling tower, known as the condenser loop, sprung a leak, rendering the system useless. Though it’s little solace to frustrated commuters, there are several emerging technologies that could have helped.

Water World

The technology improvements in buildings (and metro stations) is focused on energy. Because water is cheap, it is hard justify the expense of infrastructure to monitor it. As a result, monitoring water systems for water waste and inefficiencies is outside of the scope of most building management systems. In chilled water plants, sensors collect data on flow and temperature of water, but omit water management, such as leak detection. Seattle-based startup APANA offers a turnkey package of sensors, telemetry, and software that provide real-time monitoring of operational and mechanical water consumption. If such a system were installed in WMATA’s chiller plant, immediate notification could have been provided and downtime could have been minimized.

Another company, Aquanomix, offers a solution to collect data on water quality of chilled water plants. Though this technology would not have averted WMATA’s catastrophe, it would be beneficial nonetheless. As water evaporates in cooling towers, everything that is not water is left behind and concentrated over time as make-up water (and additional contamination) is added and evaporated. These contaminants reduce the efficiency of the chiller and cooling tower. The current method of treating them involves a water treatment technician taking physical measurements and adding appropriate chemicals to minimize impact on the system. Aquanomix uses sensors to provide real-time monitoring of water quality and integrates that information into the building management system to quantify the impact water quality has on energy efficiency.

Market Adoption

Monitoring and management technology addressing water use in buildings has lagged behind the advances made in other building operations. The prolonged severe drought affecting the western United States has started to spark a conversation around innovation in water use. However, drought may not be necessary to justify investment in better technology for water management. In Washington, D.C. (which is having one of its wettest summers), better monitoring would have improved the environment of many commuters.


Despite Bleak Chinese Construction Outlook, Still Hope for Green Buildings

— July 27, 2015

According to second quarter gross domestic product (GDP) data released by China, the miraculous decades-long growth of the Chinese economy is continuing. In reality, though, China’s GDP figures range in the territory of unreliable to laughable. As publicly traded companies announce their second quarter earnings, a picture of a more stagnant Chinese economy is emerging, and for construction, that picture is bleak.

How Low Can You Go?

United Technologies’ share price tumbled on July 21 (before receiving a little bit more bad news) as net sales and net income fell and performance failed to meet analyst expectations. The company’s Otis elevator and escalator products were projected to experience a 5% increase in orders in China for the year. Instead, the company recorded a 10% decline. The fall in elevator orders is a direct result of the fall in Chinese construction.

Unfortunately, construction in China does not appear to have a bright future. China’s government-led construction drive gobbled up massive amounts of commodities. In 2014, the country accounted for 40% of the world’s copper consumption, despite having just 20% of the world’s population. In just 3 years, China used more cement than the United States did in the entire 20th century. But, commodity prices have dropped, highlighting China’s cooling construction market. The Bloomberg Commodity index has fallen to its lowest level since 2009.

Darkest before the Dawn

Despite these construction headwinds, there is hope in high-performance buildings. The Chinese government is pushing green buildings, in part as a response to the country’s urban air pollution problem. Even though the construction boom has faded, advanced controls and building energy management systems are still poised for growth. As the focus shifts from completing construction to ensuring efficient operation, there is an opportunity for wider adoption and more sophisticated systems.

Other players in the building space are viewing China as a growth opportunity. Johnson Controls noted increased revenue on market expansion in China. Indeed, the company is investing in the Chinese market in anticipation of significant growth opportunities. Honeywell’s Automation and Controls Solutions (ACS) experienced double-digit growth in China in the second quarter of 2015. As China’s construction market continues to mature, the break-neck growth that has been characteristic has slowed substantially. The focus is shifting from more buildings to better buildings, creating opportunities for solutions that improve operational efficiency.


The Real Estate Services Shopping Spree

— June 12, 2015

You would be forgiven for thinking that CBRE stands for Can’t Buy Rapidly Enough. The company (which actually stands for Coldwell Banker Richard Ellis as a result of an interesting history of spinoffs, mergers, and acquisitions) is the world’s largest commercial real estate service and has been on a recent acquisition binge. In March, CBRE announced a definitive agreement to acquire the Global Workplace Solutions business that Johnson Controls, Inc. announced it would divest last year. Two weeks later, CBRE announced the purchase of Environmental Systems, Inc. (ESI), an energy management and systems integration provider.

Global Workplace Solutions offers services that help companies operate facilities more efficiently, optimizing real estate performance and employee productivity, particularly in the industrial, life sciences, and technology sectors. These services include everything from site selection and design, planning, and construction management to standardizing maintenance procedures and performing inventory management.

ESI, on the other hand, designs, installs, manages, and supports integrated building automation systems and building energy management systems. In 2012, ESI was selected by IBM to manage the energy use of the 50 largest federal government buildings, linking the automation systems of the buildings together on a cloud-based platform to provide enterprise-level management.

The Complete Package

Both acquisitions highlight how providing a complete portfolio of services for corporate clients is becoming increasingly important for CBRE and the commercial real estate service industry as a whole. With growing demand for green-certified commercial office space, as well as increasing awareness of the benefits of energy efficiency in reducing operating expenses, commercial real estate service providers are moving to expand their capabilities with clients. Indeed, DTZ and CoreNet Global announced a partnership that incorporates CoreNet Global’s benchmarking service into DTZ’s commercial real estate services portfolio.

Real estate services companies have historically played a less central role in energy efficiency decision-making, energy management, and energy benchmarking than other infrastructure-focused players such as energy service companies (ESCOs) and HVAC contractors. But, that seems to be changing, as corporate clients are beginning to view energy information to be as important as the other information typically provided by real estate service companies. Though CBRE’s shopping spree may be over for now, we will likely see more acquisitions by real estate services companies to fill out their service portfolios.


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