
Using buildings as batteries to accommodate more wind and solar - dnewms
https://news.engin.umich.edu/2017/09/using-university-of-michigan-buildings-as-batteries/
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samcheng
The correct terms are "load shifting" or "peak shaving."

But, in a way, they are storing energy (thermally) in a similar way to
batteries. One could imagine freezing water or condensing ammonia over night
using surplus cheap wind energy, and then releasing that stored coldness
during the day to cool the building.

I think the big objection to calling this a 'battery' is that nobody is
suggesting using that stored thermal energy to generate electricity. It's just
a way of shifting the electrical demands of the building to a time where there
is surplus electricity.

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timthelion
The title isn't just clickbate, it is a lie. There is no way to construe this
research as being a form of power storage.

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danans
It is commercial building-level demand-response, which already has been done
at a residential level in California.

DR can also be provided by fast-responding storage systems like batteries and
flywheels, which maybe explains the poorly chosen analogy to batteries.

I'm not surprised that it used more energy overall though because mechanical
systems usually are most efficient when operating at a particular speed.
Turning a huge HVAC system off and back on again quickly if it's not designed
for that would probably reduce its operating efficiency.

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Caveman_Coder
> Turning a huge HVAC system off and back on again quickly if it's not
> designed for that would probably reduce its operating efficiency.

A lot of Rooftop Unit (RTU) controls typically take an on/off command from the
Building Management System (BMS) and the BMS programming will have a deadband
range (+/\- 2°F) in which no action will occur to prevent the repeated cycling
of RTUs.

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danans
Makes sense. IIRC smart thermostats also have this sort of feature to prevent
excessive cycling of home HVAC.

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amelius
Wouldn't it make more sense to use a water basin?

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tyingq
The headline is misleading. They aren't proposing using the buildings as
batteries. They are proposing that a large number of commercial buildings
would switch on/off their HVAC systems for short periods of grid
surplus/shortfall to help balance grid demand.

The only "battery like" thing is that short durations of turning off/on a
large building's HVAC shouldn't change the internal temperature much. And
that's stretching "battery like".

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dv_dt
It's a "battery" in the grid sense that it's an energy buffer which can be
used to balance demand. If you can get over that stretch of terminology it's
sort of interesting. I've seen proposals for shifting HVAC systems to create
even larger buffers - increasing or insulating chiller fluid capacity (or even
creating large ice masses) so that during excess/low-cost power one can build
up a reserve, then cooling from that reserve during high-demand periods.

