Building Benchmarking: getting started is the hardest part.

'Benchmarking' is the only way that organizations or individuals trying to measure the energy savings their hard won retrofits or new energy efficient buildings have created, and demonstrate them to a larger world.

This important exercise can also help demonstrate to stakeholders how the organizations facilities are faring as compared to the competition's buildings, or even how buildings within a single organization compare to each other.

Over the long term, access to this information helps the facility manager develop an energy use awareness - an internal sense of how much energy makes sense for a given building to use, and how much money to expect to pay for energy in a poorly insulated rental or purchase property.

Energy labelling of buildings is one suggested way of creating this awareness. ASHRAE has created Building EQ, a program which would label buildings anywhere from net-zero energy to unsatisfactory, both as designed and as operated, and provide owners an easy means of comparing buildings to each other. ASHRAE's Fundamentals textbook, published every 4 years, also has a upper, median, and lower quartile energy performance data for a variety of building types.

Energy Star is much more established program that allows building owners to compare their buildings to all other buildings of their type registered in the program, and, solely on the basis of energy bills per square foot (adjusted for occupancy and certain other factors) learn where their building ranks. The top 25% of buildings rate as 'Energy STAR' rated. The wonderful thing about this program is that the target moves with the industry: as better buildings are built and registered, the standard moves and helps move your organization along with it to maintain certification.

Lawrence Berkeley National Labs also has a fabulous program, Energy IQ, wherein a large quantity of detailed energy data can be accessed and sorted or screened according to building vintage, exact occupancy type, and more. A larger range of building types are available in this program as compared to Energy Star's database.

In addition to benchmarking a building against other buildings, it's advisable and often fruitful to benchmark a building against itself. By choosing a reference year (if your building is that old, 1990 has the benefit of being the Kyoto treaty reference year) and continuing to benchmark your building against that one year, the effect of internal retrofits and occupant behavioural changes can be demonstrated in an easy to understand way.

When implementing occupant behaviour change campaigns, logging and providing to staff ongoing progress statements - especially if one building can be pitted against another -- can help foster healthy competition and a sense of pride in the achievements of the organization and of teams within it.

I hope that energy benchmarking becomes a part of your month-to-month energy management routine, and can provide an ongoing value with performance feedback and growth.

15 Minute Blog: Fan Efficiencies

Recently I had to select some small and some medium sized fans for a sustainable project.

The small fans were a breeze: it was a light commercial building, so I went with residential quality exhaust fans. I selected them from the Energy Star excel list of qualified fans:

http://downloads.energystar.gov/bi/qplist/vent_fan_prod_list.xls

These lists are available for all Energy Star certified equipment, and are great tools for selecting them: find a good performance index (for fans, I used CFM/watt) and then select one of the better performing, reputable manufacturers.

I put the CFM/watt effectiveness requirement right on the drawing, so that I would be guaranteed the performance I wanted from what was installed. I could also provide a good list of alternate suppliers who also meet the efficiency standard right from the Energy Star list.

The larger fans were much harder. I used a fan selection program from a major manufacturer to determine which kind of fan they sold would be in the right range for efficiency and price-point, given the parameters I needed, but the program listed a variety of different efficiencies, none quite as easy-to-understand as a CFM/watt. ASHRAE lists motor efficiency requirements, and BHP requirements, but these aren't typically provided by the equipment selection program. Without some calculations and work on my part, it was difficult to even tell if the selected fans met our standard minimum efficiency requirements. I'm not allergic to work, but if energy efficiency were considered as important as other performance indicators, our industry would have standardized ratings - the EER of the fan industry.

This problem is endemic in medium-sized HVAC products. Very small, consumer goods are being provided with clear information about operation, and are benefiting from good engineering practise to reduce energy use. Very large equipment is subject to rigorous examination by engineers for energy efficiency, and is the focus of large manufacturers for efficiency increases.

Medium sized equipment -- fans in the 400cfm - 5000cfm range, for example -- seem to be left behind by today's practises, even through the majority of Noth American commercial buildings are full of them.