> FOCUS SCALING UP NET ZERO
to found the Green Development Services
at RMI and serve on the founding board of
the U.S. Green Building Council. He has long
been at the cutting edge of high-performance
building design and development.
The Florida project is intended to be
built as a series of neighborhoods over several
decades, with each neighborhood featuring its
own ground-mounted solar array. In addition to
freeing roof space for possible solar hot water
installations, a centralized, neighborhood-wide array offers economic advantages.
“The whole question of mounting arrays
is a lot simpler if you’ve got one large array
[rather than a large number of individual,
home-mounted units],” he said. “It gives you
economies of scale.”
The idea to make the community net
zero came out of market research focused on
seniors looking for retirement homes. Pro-
spective buyers were polled on whether they
would prefer free golf (golf courses are a part
of the plan) or free energy for life.
“Eighty-five percent of the respondents
said free energy,” Browning said. “Particu-
larly if you’re on a fixed income and you
don’t know where energy costs are going to
go—that can be a little scary at times.”
Solar is the dominant energy resource for
the community, so storage is part of the plan. However, this
won’t just mean stationary batteries in basements; it also could
mean a vehicle-to-grid approach drawing on electric golf carts
while they are connected to charging equipment.
Keeping plug loads in check
One of the big issues with stand-alone net-zero buildings is
ensuring consumption doesn’t creep upward over time. Building occupants, not lighting or heating and air conditioning
systems, are generally the biggest culprits in this situation, as
they begin overspending the energy budget on coffeemakers,
desk lights, electronics and other miscellaneous plug loads.
Maintaining planned performance is an even more important
consideration across an entire district.
Pless said addressing occupant use goes back to the
basic foundation of net-zero design, which is building and
renovating structures to be as efficient as possible, with high
insulation levels and high-performing heating, ventilating and
air conditioning systems. If more is invested in the simple
passive stuff, the less one will have to depend on occupant
use patterns.
“If you’ve already got the load down, and it’s already pretty
efficient, on aggregate, that’s maybe another advantage of look-
ing across a district—you’re less dependent on
users operating the building poorly,” he said.
RMI has worked to develop market-based
concepts that provide financial incentives for
both owners and tenants to meet efficiency
targets in net zero and other high-performing
developments. Such contractual agreements can
help companies and individuals internalize the
benefits of efficiency.
“For example, in a typical incentive-aligned,
or ‘green,’ lease, the savings that accrue from
energy savings are shared between the tenant
and the landlord,” Olgyay said. “The same can
be extended to include energy generation,
where producers of electricity benefit from
selling their excess to others.”
Browning is a fan of providing occupants
with real-time consumption status in an easy-
to-understand format instead of the running
kilowatt-hour displays on a typical utility
meter. He cites a net-zero apartment com-
plex designed for agricultural workers and
their families in Woodland, Calif. Each of the
62 units in the Mutual Housing at Spring Lake
development features a color-coded energy
monitor indicating whether the occupants’
energy use is efficient (green), typical (yel-
low) or above normal (red). Those who stay
within the units’ normal range pay only a $5
monthly energy administration fee, while those who exceed the
estimate pay added charges.
Bright future for broader approach
While district net-zero planning is still at the pilot-initiative
stage, the advantages of spreading costs and load-diversity
across multiple buildings make the approach likely to become
more common. Olgyay said his organization sees a strong
future for such designs going forward—and business opportunities for electrical contractors who involve themselves in
these projects.
“At RMI, we believe creating more successful net-zero districts will result in feasible strategies for quickly increasing the
amount of variable renewables on the grid, with financial and
grid-stability benefits for the utility and the consumer,” he said.
“This is an emerging area where the market for electrical contracting can really shine.”
RO SS is a freelance writer and editor who has covered building
and energy technologies for a range of industry publications and
websites for more than 25 years. He specializes in building and
energy technologies, along with electric-utility business issues.
Contact him at
chuck@chuck-ross.com. S H
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While district net-
zero planning is
still at the pilot-
initiative stage,
the advantages of
spreading costs and
load-diversity across
multiple buildings
make the approach
likely to become
more common.