Posters: Architecture

Some Energy Savings Information for the Architect

Architects can increase energy-efficiency without huge, expensive projects. Many energy-savings measures are free or low-cost, if incorporated into the design and construction of new buildings or renovation projects. They often have with little or no aesthetic downside, and are usually easy to sell to the prospective owner. Obvious examples include reducing the number of windows on the west side of a building, landscaping the west side for shade, using light-colored roofing materials, reducing the cement around a building, and locating cooling towers away from heat sources. A sharp architect can use the projected utility cost-savings as a marketing tool.

A building comes together as the result of several engineering disciplines and building trades. In all of these, you can design out energy waste and provide permanent savings with low-cost options. Just to whet your appetite, in a moment we'll take a quick look at the electrical aspects. Going beyond electrical, you can also address such things as (and this is only a partial list):

• Building envelope.
• HVAC.
• Mechanicals other than HVAC.
• Plant systems (plant air, plant steam, chillers and cooling water, etc).
• Process systems.

With just the HVAC, for example, you can dig energy savings from a thorough examination of:

• Central chilled water plant.
• Evaporative cooling units.
• Heat pumps.
• Package and unitary systems.
• Rooftop vs. grade condensers.
• Variable speed/volume units.

Don't forget maintainability issues, comfort, security, and landscaping concerns when making changes. Failure considering these issues can result in behavior that costs more energy than you save. For example, you may remove a vent to reduce energy loss. But then operators will prop a door open.

Electrical aspects it's good for an architect to learn about

The two most common electric bill reduction techniques barely scratch the surface of what's inexpensively doable. These are the installation of energy-efficient lights, and installing power factor correction capacitors at the service entrance for a utility rate reduction. Actually, not putting these capacitors at the service entrance is smart. Instead, perform PF correction on each large load individually. So instead of getting just a utility rate reduction, you also get an actual reduction in power consumption. Just don't do PF correction on motors with electronic drives. Instead, replace the old drive with a newer, PF-corrected and harmonics-corrected drive.

Service entrance

Let's look at that service entrance, since we've now removed those capacitors and done PF correction where it should be done. For new construction, the location of your service entrance can make a huge difference. So really do a thorough analysis. For existing installations, it's usually too expensive to relocate.

Once you have a short list of potential locations that apply with the applicable clearance requirements, maintenance access, security requirements, and other issues that might rule out a particular location, examine each candidate lcoation such that you can locate the service entrance:

• Away from large heat-radiating surfaces (e.g., parking lots), hot processes, and overly moist processes (e.g., cooling towers).
• Near natural ventilation, but away from problems like cottonwood trees.
• Where later expansion with reasonable access is possible.

If you have an existing installation, you may be able to ameliorate less than optimum conditions through landscaping or equipment relocation.

Grounding vs. bonding

Architects typically don't get involved in electrical specifications, but may provide text for the general contractor as part of project duties. In such a case, the architect must avoid using the term "grounding" unless referring specifically to the lightning protection system. In fact, the best approach is to say "Ground or bond per the NEC, Article 250" in any place where you need to mention any sort of grounding. And here's why....

Facilities that have "noise problems," high harmonics, and other power anomalies nearly always have a situation where equipment is grounded rather than bonded. Consult IEEE-142, the NEC Article 100 to understand what grounding is. It means connecting to the earth.

Grounding does not establish an equipotential plane. It's vital to lightning protection. But on the load side of your service, you should not have any grounding connections. Such connections create ground loops. With ground loops, you get energy waste and potentially lethal touch voltages. For your lightning protection system, consult NFPA 780 and LPI0175.

For your load side, you want bonding. For bonding requirements, see NEC Article 250, Part V and IEEE-142. Bonding deficiencies create hazards to people and equipment. They also create various conditions that decrease energy efficiency.

Internal power distribution

Architects generally don't get involved in the internal power distribution, but may run into a situation in which they specify service entrances, transformer pads, and other major infrastructure. Since you're not an electrical expert, you may want to know a few things about this. If you were the electrical engineer, we'd tell you the following. Use it as the basis for understanding those infrastructure issues.

It's far more efficient to distribute at 480V than to distribute at 120V. To optimize efficiency and minimize energy loss, run the 480V distribution as close to the 120V loads as is practical. Today's CAD programs allow you to experiment and see what works best. So, do that. Try various locations for the various 208/120V panels to see how you can get the shortest runs. It may be worth breaking up things into smaller transformer and panel arrangements fed by longer 480V runs than to use one large central 208/120V panel in a building or large room. Yes, you'll incur higher engineering costs, but you may easily earn those back through construction cost savings. Smaller switchboards, breakers, conductors, and raceway cost less and are typically easier to install.

You might be using 277V for HVAC reheat boxes or lighting. If possible, change these out to 480V. Else, use small 480-480/277V transformers to derive 277V as close to these loads as is practical. Follow a similar strategy with 120V loads.

Generally in a commercial building, 480/277V feeds the infrastructure, and 208/120V feeds everything else. Generally in a factory, 480/277V feeds the the infrastructure (including plant air) and production equipment, while 208/120V feeds controls and offices. If you have 120V lighting, start thinking about upgrade projects.

Now at this point, there is more we could discuss about feeder circuits. And we haven't even started on branch circuits.


So, there you have an introduction to electrically-related energy savings that result from good design choices prior to construction. The typical electrical contractor doesn't know about these things, though some do. If the client is highly interested in gaining permanent energy savings, we do offer consulting services along these lines. Write to Mark at sales@mindconnection.com if you would like to provide such benefits to the building owner.