A Discussion on Occupant Engagement, Part II

(This is the second post in a three-part series, see part I below)

Q: Have you calculated a $ per KWh cost of the efficiency/savings vs the cost of the Pulse software?

APS: Not yet, but I would like to do so. It would be important to measure the persistence of savings first. This is something we will do in our second campaign. After that, we could come up with an estimate of the 52 week average energy savings percentage (over and above the pre-Pulse/campaign baseline) and apply that against the total electricity bill. In 2008 (pre-Pulse), our Ministry (about half of the building, plus other buildings) consumed 4828 GJ of electricity. In 2009 (post-Pulse), that figure was 3136 GJ, a saving of nearly 1700 GJ or 472 MWh. However, we need to normalize this figure to remove other buildings, different staffing levels, etc, so I don’t want to attribute all the savings to the retrofit / Pulse / campaign.

Q: How much money was spent on installing light switches, dimmers and occupancy sensors, and implementing Pulse’s monitoring software/hardware? And how does this amount compare with electricity cost savings?

APS: The lighting retrofit was approximately $100,000. We have a declining block rate structure that puts all savings (unfortunately) in Step 2, making it very challenging for any lighting retrofit to be cost-effective.  In addition, the pre-existing lights are T12 with electronic ballasts.  Replacing magnetic ballasts is far more cost-effective. The monitoring hardware and Pulse software was a small fraction of the cost of that overall bill. The reason why we did this was to demonstrate leadership, albeit the only way to transform the market is to fix the rate signal with an inclining block rate structure so that such investments become cost-effective.

Q: New cell phones chargers only draw about a watt. Is it really worth turning them off?

APS: You are correct. More appropriate plug loads to target are speakerphones and printers.

BM: That said, getting people in the habit of unplugging/turning off anything when not in use will help yield larger cumulative savings. It also saves them from having to think about which items are ok to leave on vs. which ones need to get turned off. Make the choice simple for them. Most items at a person’s desk consume relatively small amounts of electricity on their own. However, giving people an action they can do, something they have control over, will engage them in the process of conserving energy in their workplace. If they are willing to do the small actions, they are more likely to do larger, less convenient actions (like giving up a personal printer.)

Q: can you use light intensity meters and compare lighting consumption over light intensity in the office to detect ways to improve efficiency?

APS: yes, probably. We hired an engineering firm that specializes in lighting to assess the level of lighting. Interestingly, many employees will remove fluorescent tubes if their space is overlit.

Q: can you use theoretical watt per meter square per year of lighting for example as a target?

APS: Yes, absolutely. We haven’t done that yet, but would like to. We could use the ASHRAE/IESNA 90.1 standards for lighting power density as a guide.

- Julius Walczynski