Special Report: 5.14.2009
Posted by TED Magazine
on Thursday, May 14, 2009
Zero is as Zero Does
By Joe Salimando
There is more and less than meets the eye in the phrase “Net Zero
Energy Buildings” (NZEB). I did not suspect this in late March, when I
got on an airplane and attended a conference on NZEB sponsored by ASHRAE.
Many people learned a lot at the conference, and your humble reporter is one
of those who learned even more than that (a heck of a lot?). I had pretty much
ignored NZEB. What little I knew as of mid-March told me that I liked it.
I was both right and wrong.
Maximize Energy Efficiency
Terms associated with NZEB include “zero energy homes.” The terms
can confuse, in and of themselves. A “zero energy” building sounds
like it’s completely disconnected, but that’s not what it’s
about. A NZEB is one that sells energy to the grid sometimes and sucks energy
off of it other times, with a “bottom line” of zero.
At least, that’s my understanding. There is no hard-and-fast definition
(I learned that at the conference, when one speaker provided four levels of
NZEB to shoot at).
Electrical people (and others) should really fall in love with NZEB. Why? The
goal is not to build some humongous solar or wind installation and attach it
to an office building, warehouse, or home. The goal is to minimize the building’s
energy consumption.
Among other things, one needs to be smart about lighting to do that. Yes, maximizing
use of daylighting is part of the trick. But so are state-of-the-art lighting
fixtures and bulbs, smart lighting control, occupancy sensors, and more.
Several speakers said the same thing: Because the solar PV installation
you put on the building is going to be expensive, we have to get the building’s
electrical use down to an absolute minimum—so you can downsize the
PV install needed to get to zero?
Yes, this should be music to the ears of electrical manufacturers, distributors,
and contractors. It also makes a lot of sense.
Above: The chart shown was much-displayed (usually one of
the first 4 slides) by various speakers at ASHRAE’s conference on NZEB.
The specific slide above came from the presentation of officials from the National
Renewable Energy Lab.
Contrast with LEED
As noted previously, I'm
not a big fan of LEED. No, I’m not anti-USGBC or any such thing. But
I find LEED’s focus on design intent wrong. (The key is performance.
It’s just dumb to award LEED certification to a newly constructed building—building
energy performance over time should lead to an award, or not.)
Add: Damn few of the nation’s millions of existing buildings are even
candidates for certification under the LEED-EB process.
If someone at this conference said something bad about LEED, I missed it. However,
the clear focus here was on energy measurement and verification, shorthanded
as “M&V.” At some level, the speakers seemed, as a group, obsessed
with counting every damn kilowatt-hour.
I listened as one engineer talked about designing a school building for NZEB,
and having it exceed (by some number of kilowatts) zero. What was the reason?
Security lighting was added in the parking lot; that wasn’t in the original
plan. And a number of marketers offered attractive deals if the school accepted
some vending machines; the machines used power (every doggone day) and that
wasn’t in the original calculations.
Does this seem an incredible level of detail? Someone who is serious about
zero, I learned, is bothered by any number above zero. That message came through
loud and clear; these folks are into binary reasoning (you did zero,
or you didn’t).
Above: California projects huge decreases in emissions per
person over the next 40-plus years. Don’t put it past the state; while
electricity use has increased all around the country, California has, over recent
decades, turned its energy-use graph (not shown) into a flat line.
What’s Coming on NZEB
California: State law says all new residential buildings built
by 2020 must be NZEB. That seems really important, doesn’t it?
Home to 36.76 million people as of 2008 (Census
data), the state has added 7 million (23.5%) since 1990. An estimated 23
million-plus are to be added by 2050 (see
2007 report). So the state will have 60 million of the 438 million U.S.
residents in 2050.
California’s law also calls for all commercial buildings built in 2030
and thereafter to be NZEB.
Above: EUI = energy use intensity. This graphic shows existing
commercial buildings at 90,000 Btu per square foot per year right now. Were
all commercial buildings built to code, the nation could get down to less than
half that—40,300 Btu per square foot per year. The idea of NZEB is to
get down to that lower number (12,200), and then provide that energy with solar,
wind, or some energy alternative.
To restate: By 2030, new buildings built in the nation’s largest state
must be NZEB—all houses and commercial buildings that are built new.
California also has a retrofit goal for commercial buildings, which Dian Grueneich
of the California Public Utilities Commission presented as “50% existing
buildings equivalent to ZNE buildings by 2030 through deep efficiency and clean
DG.” The plan is to retrofit 250 million square feet annually (which is
5% of the space in the state’s existing commercial building).
California’s PUC has erected an EE
website, where you can download (110p PDF) the state’s long-term EE
strategic plan.
United States: In a little-noticed (by me, anyway) set of provisions
in the Energy Independence and Security Act of 2007, the United States
is supposed to:
- Go NZEB for all commercial buildings constructed by 2030 (that’s
nationwide!)
- Get to NZEB via retrofits on half of commercial buildings by 2040
- Add the other half, via retrofits, by 2050
If those legislative goals are met—which is one heck of a vision, theory,
or fantasy (take your pick)—all U.S. commercial buildings will be NZEB
by 2050.
What was encouraging, to your humble reporter, was that the governmental speakers
at the NZEB conference were technologists, not regulators. The focus was on
how to achieve net zero, not how to tighten the rules and laws to get people
to go faster and go further toward these goals.
Joe’s Problem with NZEB
Let’s play pretend and let’s do some math. Let’s say all
commercial buildings built in the United States from 2030 on are NZEB. By 2030,
the construction industry has its act together; we can and do construct buildings
that do not add stress to the grid.
OK. Your next question should be: What impact will that have on our national
energy consumption? After all, that’s the goal, isn’t it? Most
of this is being pursued in the hopes of “doing something” about
the specter of global warming.
Here’s what we get accomplished: Each year, we add about 1% to 2% (in
square footage) to the nation’s commercial building stock. It’s
not clear (to me) how much we retire each year, but to simplify the math here,
let’s say:
- The number we add and retire is the same, more or less
- That number is 1.5% a year
Okay. How much of an impact will this new-construction change have on building
energy use between 2030 and 2049 (i.e., the first 20 years of NZEBs) on the
commercial front?
Answer: 1.5% x 20 = 30%. Our national building stock at the start of 2050,
under this extremely hypothetical scenario, would be 70% old wasteful buildings
and 30% NZEBs.
Therein lies a rather obvious problem with the NZEB idea: It’s not
going to happen fast enough, primarily because the attack here is on newly
designed buildings.
In comparing approaches here, I go beyond looking at LEED and NZEB. I’ve
become a big
fan of Ed Mazria, who proposed making a major effort—starting next
week, for Pete’s sake!—on doing energy-efficiency retrofits
of existing buildings. With federal funding.
What about the California (and national) plans for retrofits to improve the
existing building stock? I don’t believe these will work; in fact,
I don’t believe they will even be tried. New buildings need permits and
connections to sewers, water systems, and the grid. Builders/developers must
jump through whatever hoops are erected.
In contrast, existing buildings already...exist. Is it reasonable to believe
that our governments (national, state, local) will journey to the extreme of
fining or turning off existing building that do not comply?
It seems extremely unlikely to me. Mazria’s idea might work. The
Salimando Solution is best, of course (he said, immodestly)—a stupendous,
overnight increase in energy costs (say, electricity at $1 per kWh, or maybe
more).
Assumptions, Presumptions & Credibility
Let’s presume we are strategic thinkers and think global warming is real.
What to do?
- We must get the Chinese and Indians NOT to develop their countries to be
wasteful and inefficient...as we are.
- We can’t tell 2.4 billion people what to do.
- Therefore, we need to convince them by our actions.
- Conclusion: We must walk the walk on global warming and energy efficiency...so
they’ll believe us, and act accordingly, when we talk the talk.
Now put that conclusion next to the statistics above: In the unlikely event
that every single brand new commercial building built after 2029 is an NZEB,
by 2050 it seems likely we’ll still have 70% of our buildings be of the
bad old (energy-wasting) vintage.
Where’s our credibility? If you’re a decision-maker in China,
would you pause (for even half an hour?) to listen to us on global warming?
Or would you just continue on your merry way, building more coal-burning plants,
inefficient new buildings, and such?
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Joe Salimando of EFJ Enterprises is a consultant, web content provider, and wordsmith based in Oakton, Va. To contact him, call 703-255-1428. See also The EleBlog.
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Personal Disclaimer: The appearance of the ambling pachyderm is indicative of the writer’s obsession with elephants, not his political leanings.
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IMPORTANT NOTE: THIS COLUMN REFLECTS ONLY THE OPINIONS OF ITS AUTHOR AND DOES NOT REFLECT THE OPINIONS OR POLICIES OF NAED, TED MAGAZINE, OR THE ADVERTISERS ON THE TEDMAG WEB SITE.
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