Noel's Green (make that SUSTAINABLE) Blog » Building Performance

Building Re-commissioning

noel — Thu, 22 Jul 2010 17:12:52 +0000

A review of

Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse Gas Emissions
By Evan Mills, Ph.D.
Lawrence Berkeley National Laboratory for: CEC (PIER) July 21, 2009

This white paper contains some compelling arguments in favor of re-commissioning. Money and energy are two items. A building is a kind of organism. We tend to forget that nature and behavior tend to tear and break things down. The passage of time wears things out and we have to maintain our buildings, and just like cars, they need to be tuned up regularly. It’s amazing how much money is being lost by neglecting to do a tuneup. Government and institutional buildings are especially prone to this benign neglect. In government, its often a case of out of sight, out of mind.

A Flow Chart for commissioning

noel — Thu, 08 Apr 2010 19:57:57 +0000

Alright, I will get off my high horse now and back on my regular horse. Back on the subject of energy and high performance buildings. Recently I have had the good fortune of connecting with some very good people and I am busy again at my profession. I am working with a great commissioning team doing LEED projects. I must say, it is gratifying to be using my experience and brains for a good cause: making a better built environment.

Here is a flow chart that I like. Charts are great for reducing complicated processes down to one glance… I like a good flow chart because they are visual, and I tend to be visual, maybe because of my defective ears.

This chart was borrowed from ASHRAE by the National Institute for Building Sciences (NIBS), and is posted on their Whole Building Design Guide web site. Click on the thumbnail to see the full size version.

How to Sustain the Energy Efficient Design

noel — Mon, 01 Mar 2010 05:40:35 +0000

I am worried now. A new report just came out showing that 85% of CMMS (Computerized Management and Maintenance System) software being purchased is not being used. This is software that is supposed to be used by facilities managers to streamline their work, but apparently without much eagerness.

An excellent commentary in this months Engineered Systems magazine, entitled Tomorrow’s Environment: A Failure to Plan Is A Plan To Fail by Howard McKew, exposes the weak link in the chain between energy efficient design and the long term operation and maintenance of said design. How do we know they are getting what they paid for?

Too often, we don’t know. McKew explains that measurement and verification is often left out of the design due to budget constraints. I think operations often falls under the radar for lack of understanding the need for verifying. And CMMS software, intended to help rectify this problem by making it easier to manage and maintain the many moving parts of a building, apparently doesn’t get used!

I have mentioned ACCOUNTABILITY in previous posts, and here is another sample of what I am talking about. My worrying is well-founded. Filters need to be changed, pump bearings need lubricating, dampers need to be observed in operation, temperature sensors need to be calibrated and so on. HVAC, even when it is designed to be as simple as possible, is still complicated in practice.

Report Dispels doubts on Conservation Measures

noel — Sat, 13 Feb 2010 16:43:20 +0000

This Lawrence Berkeley National Laboratory report, Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse-Gas Emissions should inform the skeptics about the efficacy of this process for buildings. Regular tuneups for your car are the norm, so the same should be for your building.

I quote:

“This report responds to a widely held concern that end-users do not have confidence in the nature and level of energy savings that can be achieved through the commissioning process.”

This is what I think of when they say “sustainable”: The report states that there is a 16% median annual rate of return on investment for existing buildings and and 13% median annual return on new construction. EXCELLENT. How many other investments bring in that rate of return on a sustained basis?

The report continues:

Applying … [this] to … non-residential buildings corresponds to an annual energy-savings potential of $30 billion by the year 2030… An industry equipped to deliver these benefits would have a sales volume of $4 billion per year and support approximately 24,000 jobs.

EXCELLENT!

Modularity and HVAC systems design

noel — Thu, 11 Feb 2010 03:53:59 +0000

Simple is as simple does. It works. Its easier to understand. Easier to fix. The real world does not reward complexity.

An important aspect of good design is simplicity. HVAC can be complicated enough, given the need to maintain various spaces at set temperatures, relative humidity and cleanliness. HVAC systems are also expected to maintain certain pressurization and [code required] outside air exchange. All while keeping to the highest possible energy efficiency. We also need and expect them to respond precisely and correctly to changing variables.

Simplicity in controls are also key to this. The simplest controls are on-off. Simplicity is not obvious everywhere. But in reality, as software development theory teaches, you can find the simple by decomposing the complicated.

Consider these concepts before the initial Basis of Design is established. Decompose the various functions needed and decide how the system will be controlled. Many designers have their personal preferences and presumptions, but these must be put aside in favor of open-mindedness in the beginning of the decision making process. Yes, energy and size calculations may be useful, but not as important as what and how to control the various environmental parameters.

Diagrams of the systems,

Mass-flows, temperatures, and pressures. For lighting, its watts and lumens per square foot. And using natural ambient light wherever available.

Get these right the first time, and you will save all kinds of hassle. During design, keep the diagrams as a guide and reference. It will keep also you focused and directed.

Next subject: Dedicated outside air systems (DOAS) These kinds of systems separate the ventilation "function" from the building internal HVAC. Tens of millions of buildings have no way to split this from the basic heating and cooling. Which makes the controls complicated. DOAS is especially good for high occupancy rooms and in situations where air change requirements are more exacting. Its an economic question and we have to decide how and whether this is worth the trouble. Most significant in schools, assembly rooms, theaters, health care,

In many existing buildings, DOAS, which require separate main ducts, may be impossible to retrofit due to space limitations and structural issues. But DOAS divides the work that HVAC systems do, they can be used to recover energy that is lost by exhaust systems. Furthermore, because DOAS central units can be physically remote, so they do not contribute noise to the occupied space and finally, they incorporate the potential to increase net rentable space!

An alternative, if the above is not economically feasible, is to keep and/or update the existing systems, measure carbon dioxide levels (a proxy for stale air), and control the entering outside air according to that parameter. This is "Demand Controlled Ventilation" control, which I described in this previous post in November.

Better HVAC can save $48 billion/year in the USA

noel — Fri, 05 Feb 2010 21:16:55 +0000

The latest numbers are that US buildings consume $320 billion/year in energy. 2/5 of all the energy used in the US. And about 40% of the energy (costing $120 billion/year) is used in buildings for HVAC.

Some of the 2009 stats HVAC designs that I have incorporated recently into my office building projects are expected to use 30% less than the levels allowed by the local and state building codes. (ASHRAE Energy code 90.1-2004).

Consider that more than 70 percent of existing commercial buildings in the country were constructed prior to 1980 (according to floor area, see this 2001 study) . It is very likely that most of these older buildings consume well over the present building code allowable.

There are no laws requiring them to retrofit. The financial incentive to retrofit is all that exists, and unfortunately, this is another example of out-of sight, out-of-mind ignorance. (and HVAC and building energy use in general getting no respect).

These buildings should be retrofitted to reduce energy use a minimum of 30% and more. Up to $48-60 billion per year is being simply wasted. Wow! That is $200 a year for every man woman and child in the US. Almost half as much as we throw away on the war in Iraq. ($130 billion in 2007)

Hey, what are you waiting for, lets find out where the energy is going!

Lighting… I did not mention lighting: higher efficiency lighting and optimal daylighting could save ANOTHER $20 billion /year easy.

If you still a skeptic, please read: “Working Toward the Very Low Energy Consumption Building of the Future”

Getting a View of Energy Consumption in your building

noel — Wed, 03 Feb 2010 21:58:13 +0000

Trends: Read the chart on your buildings energy usage. Monthly charts can usually be found on the monthly utility bills. Your utility company can provide them upon request (usually). If and when you can acquire the hourly or daily usage charts, the pattern of usage can be very revealing about whether your building is running at its best. What does a trend chart look like?

An example of a daily building trend chart

The US Department of Energy has a gather and track data process listing the following steps.

STEP 2: Assess Performance
* 2.1 Gather Data
* 2.2 Establish Baselines
* 2.3 Benchmark
* 2.4 Analyze Data
* 2.5 Technical Assessments & Audits

Here I am only discussing Step 2.1, ‘Gather data’.

Daily and hourly charts are more detailed require additional metering devices. This may be problematic, as mentioned further down.

If your building has a control center, it is very possible, and indeed likely, that the consumption patterns can be found in the computer logs. But in many older buildings, this may be problematic. This is where upgrades should start.

Deciding on what to measure and then installing the meters and using the data correctly is the key. It starts by studying the building systems, and deciding what wires or pipes are carrying the energy in question, and installing the meter(s) in the correct physical location.

Next, installing a communication link between new and old meters and a data collection center, such as a desktop computer, creates the data collection network that is needed. The cost of this approach is extremely reasonable, and in fact, with IP networking, whether hard wired or wireless, it is an incredibly simple and cheap way to get a handle on this.

Having the data in hand will help. But one must understand how the building system in question is being controlled. The charts can be complicated. But decomposing the building systems down to their simplest points will yield a lot of valuable information once it is charted. Having your building engineer or an outside consulting engineer experienced in HVAC controls is often necessary.

More reading about energy measurement and metering and a prior article on measurement in Noels Green Blog.

What are we measuring?

Motors, lights and electric resistance heaters are the major electric energy consumers. Boilers, unit heaters and furnaces are the major gas/oil consumers.

Of course, a major component of electric use is the ‘plug loads’, which is equipment actually plugged in. These are usually in the control of the user/occupants themselves. They include computers, task lighting, televisions, refrigerators and so on.

Electric heaters are often being used by user/occupants who feel cold and do not get their complaints/needs heard or met. This is unfortunately, a ubiquitous problem in the USA, just now getting serious attention after years of ignoring.

The next wave

Now here is a very nice “downstream” application for building information modeling. It is not getting much attention. Yet.

The same Building Information Model which is being used to design and build with, can easily be re-used as a framework for the building control center! Why not have the metering and all other energy systems mapped in the BIM? You would have a ready made view of the Building Energy Consumption!

This has been a theoretical possibility for many decades, but the cost and complexity of it was such that no one besides a NASA or a nuclear research lab could implement it. Now we have a chance to see the possibilities of such high powered data collection and analysis being done on a desktop computer. Hooray for IT!

Attention general public : Buildings have the greatest energy footprint, not cars

noel — Wed, 27 Jan 2010 18:33:30 +0000

The guys over at Autodesk made this cute animation to drive the point home

The Buildings Sector accounts for about 40% of U.S. Energy, 72% of Electricity, and 34% of Natural Gas use. Building energy costs totaled $390 billion in 2006.
The Buildings Sector accounts for about 40% of U.S. Energy, 72% of Electricity,
and 34% of Natural Gas use. Building energy costs totaled $390 billion in 2006.
Source: Buildings Energy Data Book, Sept. 2008

30 years versus a certain curriculum.

noel — Fri, 22 Jan 2010 06:19:20 +0000

I want to clear the air about something that has been problematic for years. I do not have the standard degree in my field.

Recently I have been in close contact with many engineering, architecture, and construction hiring managers. The communication has revealed much and disappointed me on a number of occasions as I seek a new employer.

It’s the BSME. Employers are fixated on this credential. Filtering talent based on the degree-type parameter is not always justifiable. The filter does not do justice to the tremendous personal capacity and energy I bring to help make things happen. I have not been lucky in my search, anyway.

There is a serious shortage of good engineer talent. I bring a capacity to handle and coordinate many varying and complex issues of building design and making them benefit all.

MEP design is complex, no doubt, and a great degree of trust and reliance is placed on the project engineer. I am intimately familiar with the design process. I know how to make a design constructable. I promote and enforce high efficiency (LEED certification and Energy Star rating), and otherwise, I always strive to deliver “high performance” solutions.

Experience is the great leveler. I want to make this perfectly clear. My 30 years of practical HVAC and electrical design and build experience is at least EQUAL to the knowledge gained from a 5-year BSME. I bring a lot more than a general engineering knowledge to the table.

So how did this happen? A: In my life, engineering curriculum’s were not available to me when I was ready, willing and able.

I went to college after high school expecting to be an architect. When I attended Miami U, the world was changing and so was I. I was not as great an architectural designer as I thought I was. By the time I graduated, many opportunities and assumptions that seemed inevitable at the beginning had vanished. After I graduated and took my first job as a controls design /draftsman, the path was clearly leading toward consulting engineers, HVAC and electrical design.

When I decided to go back to college for a second degree, in 1996, the electrical engineering (only) curriculum at University of North Florida was small, and seemed stifling. After much deliberation, I concluded that a wider study of information science was more relevant to my future. So the die was cast.

THE LAST ENERGY CRISIS- 1970s and a B.S. Environmental Design

noel — Tue, 19 Jan 2010 18:10:53 +0000

I have a BS ED, which is a science that encompasses the junction between engineering and architecture. My expertise is in buildings and how they work. I focused all my career on design of the built environment and building systems. I was educated in energy conservation, neighborhood preservation, and solar energy in the 1970s. I was trained to create design solutions for all kinds of advanced issues like

active and passive solar heating,
air conditioning,
historic building preservation
human factors like indoor air quality

I first learned how to do an energy model with pencil and paper. It was very exciting to learn how to design and justify energy conservation measures. Then the Energy Crisis went away about 1982. The energy recovery methods that I thought were so cool were no longer needed or cost effective. But the career path open to me was still basically HVAC controls and design. So, this is what I did, and this is what I do.

To be sure, most, if not all, of my professional peers are schooled in mechanical engineering. ( and they possess a B.S. Mechanical Engineering). I do not have that specialization. However, I am uniquely qualified and experienced.

Like many professional engineers today, my desire is to serve the design and construction industry. Many people do not remember the 1970s. I prepared for an energy shortage then, and I remain ready to help attack the problems of this new energy crisis.