Big buildings’ energy consumption and demand is managed differently in Australia than here in the U.S. There are many reasons, like more expensive energy, higher demand charges, peaks that can be set annually, better metering etc. With experience in both countries, I have seen first-hand that premium offices in Australia manage energy more actively than their peers in the US, and some argue more effectively. GRESB survey results and the continued increase in the average office building energy rating (via NABERS) would seem to back them up.
So what happens when Australia gets blasted by an unprecedented heat wave and these buildings are really tested? How much energy do they use when its 110 Fahrenheit (43 Celsius) in Sydney? How do those supposedly well run premium office buildings fare?
Pretty damn well, actually. From the Buildings Alive blog – “Is peak demand growth really inevitable?”
“Despite the challenging conditions, 18 of the 36 Sydney office towers we’ve been helping to manage demand have achieved lower peaks than they recorded last year. The average increase was 0%. This is good for the environment and good for network stability. It is also good for the bottom line – combined, the buildings’ facilities managers have shaved 3,000kVA (~3MW) off the network peaks and will save their owners an average $12,000 per building in capacity charges over the coming year compared to what they would have paid if they had done nothing special.”
So on average, these buildings DID NOT increase their peak from the previous year, and half of them actually set LOWER peaks! Buildings Alive sends out “Peak Demand Forewarnings” up to three days in advance when their models suggest a building is in danger of setting a new peak. BA service engineers have worked with the FMs to put plans in place for dealing with these extreme conditions.
It is not like these buildings defied physics. They just pre-cooled spaces overnight, modified weekend set points, and tried to smartly ramp up and “coast” through the hottest hours. And of course they delayed energy use that could be delayed without impacting building occupants.
And we are pretty sure what would have happened without those changes:
“Ordinarily, such conditions would cause electricity demand to rise by roughly 8-10%*, as the AEMO data suggests. But is demand growth inevitable? Or, put another way, with sensible preparation and reliable forewarning of peak conditions, can over-investment in infrastructure and the dangers of blackouts be avoided?
(* We have found that for every 1 degree [C] increase in indoor-outdoor temperature differentials during summer, HVAC load increases by approximately 6%. This corresponds to roughly 3-4% higher base-building demand from office buildings for every degree increase in ambient temperature.)”
Now to speculate a bit, what would happen in the U.S.? If it hit 110 degrees F in New York? Are commercial building operators ready?
Hard to say. Our systems for “demand response” are different, but I do know that many facility managers give very little thought to peak demand events, and they generally do not have a strategy to avoid setting new peaks. But should they? I’m of the opinion that FMs should always make strategic changes to building operations so that the adequate conditions are provided to occupants, if at all possible, at maximum efficiency. This is true for heat waves just as much as it is true for opportunistically maximizing free cooling during nice weather. A building should always strive to run at its optimum efficiency in the conditions it faces. Put another way, there is no downside to active, informed, and prepared facility management.
Let’s hope we still have a while to study before we take this test!