Transformers: Problems in Disguise

Sometimes a significant source of energy inefficiency in a building can be hiding in a place difficult to detect. In some buildings, a single transformer can have a substantial impact on electrical consumption.

Image of currents flowing through a transformer

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Some Background

Transformers are responsible for stepping the incoming voltage to a building up or down depending on the design, intended use, or connected equipment.  A standard electrical socket in a US home or office will deliver 110-120 volts AC. Some appliances require 240 V instead. Large mechanical equipment, such as the air handling units, distribution pumps and chillers found in commercial or multifamily buildings may require 460 V. In buildings where the incoming voltage from the utility does not match the voltage required by connected equipment, a transformer is used to deliver the necessary voltage.  The voltage entering the transformer is called the primary voltage and the voltage delivered by the transformer to the facility’s equipment is called the secondary voltage.

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HomeFree – A Healthy Material Resource for Affordable Housing Leaders

Healthy Building Materials as Contributors to Overall Human Health

Healthy Building Contributes to Human Health

What do you think of when you hear the term “healthy living?” A balanced diet? Physical activity? What about healthy building materials? The concept of healthy living can — and should — be extended to include anything that can affect people’s health either directly or indirectly. With this in mind, the impacts of building materials on occupants’ health is a growing concern of building industry professionals because exposure to unhealthy chemicals used in building materials can trigger serious health hazards.

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What’s new in LEED V4 – Commissioning Changes

The sunset date for LEED 2009 project registration has come and gone and all new LEED registrations (or existing registrations that will not submit for preliminary review before June, 30 2021) will fall under the V4 rating system. We are still seeing a trickle of requests for LEED 2009 compliance support for projects that were registered before the October deadline, but those are becoming few and farther between. At the same time, design and construction teams are still wondering what the differences are between the rating systems. So, we are highlighting a few changes to the commissioning requirements in LEED V4 BD&C about which Architects and Developers should be aware.

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Nanogrids: A Whole Building Approach to Distributed Energy Resources

Distributed Energy Resources
Distributed Energy Resources (DERs) are a growing part of the energy landscape in the United States, and they are becoming an ever more attractive opportunity for households, companies, and building owners to gain control of their own energy needs. By 2024, it is estimated that solar PV plus energy storage will represent a $14 billion industry [1]. These resources are installed on the customer side of the utility meter and include distributed generation, such as combined heat and power (CHP) and solar photovoltaics (PV); energy storage assets, such as batteries; energy efficiency and demand management; and building energy management software. When deployed correctly, DERs have the potential to reduce the carbon footprint of the electric grid, increase grid reliability and resiliency, and defer the need for costly upgrades to grid distribution and transmission infrastructure [3,4,7]. Read more

VRF Systems vs. Electrical Resistance Heaters – A Case Study

Variable refrigerant flow (VRF), also known as variable refrigerant volume, was a concept developed by Daikin Industries in the 1980s. The technology is based on transferring heat through refrigerant lines from an outdoor compressor to multiple indoor fan coil units. VRF systems vary the amount of refrigerant delivered to each indoor unit based on demand, typically through variable speed drives (VFDs) and electronic expansion valves (EEVs). This technology differs from conventional HVAC systems in which airflow is varied based on changes in the thermal load of the space.

The two main VRF systems are heat pump systems that deliver either heating or cooling, or heat recovery systems that can provide simultaneous heating and cooling. These two applications, plus the inverter-driven technology of the outdoor compressors, allow for greater design flexibility and energy savings. In applications where heating and cooling are simultaneously called for in different zones, VRF heat recovery systems allow heat rejected from spaces that are being cooled to be used in spaces where heating is desired. Read more