Building Energy Efficiency and Sustainability Flashcards

Which ASHRAE standard sets energy-efficiency requirements and energy use targets for existing buildings?

Answer: Standard 100

Standard 100 covers energy efficiency in existing buildings, including EUI targets and operating requirements.

Under ASHRAE 90.1, demand-controlled ventilation is generally required in spaces larger than 500 ft² with a design occupancy of at least:

Answer: 25 people per 1,000 ft²

90.1 requires DCV in spaces over 500 ft² with a design occupancy of 25 or more people per 1,000 ft², with some exceptions.

Which ASHRAE standard provides the climate zone data that 90.1 uses to assign envelope and equipment requirements?

Answer: Standard 169

Standard 169 provides climatic data and defines the climate zones that 90.1 references.

Why do energy benchmarking programs often report source EUI rather than site EUI?

Answer: Source EUI accounts for generation, transmission, and distribution losses, so different fuel types can be compared fairly

Source energy converts each fuel back to raw primary energy, which makes buildings with different fuel mixes comparable.

Which IPMVP option relies on a calibrated whole-building energy simulation to determine savings?

Answer: Option D

Option D uses calibrated simulation and is useful when baseline data is missing or the measures interact.

What is the main energy benefit of a thermal energy storage system, such as an ice storage system, in a commercial building?

Answer: It shifts cooling load from on-peak to off-peak hours, which lowers demand charges

TES makes ice or chilled water at night and discharges it during peak hours, which cuts peak demand and cost.

In ASHRAE Standard 34, what does the refrigerant safety class 'A2L' mean?

Answer: Lower toxicity and lower flammability (mildly flammable)

A means lower toxicity, and 2L means lower flammability with a low burning velocity, as with R-32 and R-454B.