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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Designing Solar for High Density Areas

Hear the term “solar energy” and you’re likely to think of vast fields of glistening panels and hillsides transformed into disco balls. Hear the term “solar energy” and you might picture suburban McMansions with roofs that reflect the sky. Hear the term “solar energy” and you envision… skyscrapers? Affordable housing units? Clusters of panels lurking in the crevices of a city skyline?

By 2050, solar energy is projected to be the world’s largest source of electricity, and it would hardly be reasonable to do so by means of blanketing entire stretches of usable or natural lands with sheets of silicon. Instead, part of the solution lies in designing solar for high density areas, which is quickly becoming the backbone of the solar boom, providing access to, and availability of, solar energy in densely populated areas.

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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

Power vs. Energy

I can get worked up about units, and this can really annoy people. It especially annoyed students I taught in grad school. I was pretty tyrannical when grading; they always had to include units in their calculations. They could have all the right numbers, but they didn’t get full credit unless all the units were right too. I have no regrets about being such a stickler, because I see tons of confusion about this in the building & energy fields. So here’s a rant about one of my pet peeves: power and energy.

Question: What’s the difference between Power and Energy?

Is this some kind of philosophical question? A koan to meditate upon? No. There’s a real answer (in the engineering world at least). Power is the rate of energy.

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