Concentration of CO2 in the Atmosphere

The missing element in all energy audits

The missing element in all energy audits continues to be the lack of an Energy Use Goal of any kind, ZEB being the best energy use goal for planning every project.

These energy audits are focused on short term return on investment without any energy use goals, except the general goal of some reduction on energy use. There is a note about savings increasing as the cost of energy goes up. Any 8-10% savings will be swallowed up by even a small increase in the cost of energy. So, although the return on investment looks good on paper, the reality of finite financial means coupled with increased cost of energy leaves the owner with little short term and no long term change in their financial stability. As soon as the cost of fuel goes up they are strapped to pay for it. So their reality is “I just invested to have this work done, I’m better off than I would have been, but heat is something I have to pay for and the recent 30% increase in the cost of heating leaves me strapped to pay it. What do I do now? Have another energy audit to see what is the next best return on investment?”

Note that within the 1st couple of sentences of many energy audits there is a statement the shows the key driving force “someone is currently providing cash incentives”. The energy audits seem to be focused on what minimum will get the incentives, not what will achieve an energy use goal. No client was asked what energy use goal they want to achieve, ZEB being an example of an energy use goal. All current energy audit training and field practice leaves the client separated from participating in any way that would establish their energy use goal as a foundation for the energy audit. How much energy use reduction is achieved by energy audit proposals is totally up to what the auditor seeks to “sell” the client as work worth doing. I guess the average decrease in energy use as a result of work proposed in energy audits is between 8% & 20%. There is an effort to get to 35% by giving some extra incentive $ if it is achieved. So, if an existing home or building has a HERS Index of 350 and the improvements achieve 30% improvement, then the HERS Index will come down to 245. A substantial improvement, but lets look at it in context of other goals that make use of the HERS Index. If the same building achieved the performance of the energy efficiency code, then it would achieve a HERS Index of 100. Energy Star requires achieving a HERS Index of 80 or less. ZEB requires achieving a HERS Index of 30 or less. So this 245 Index for this building is about 1000% (10 times) more energy use than ZEB, or about 300% (3 times) more energy use than Energy Star threshold, or 245% more energy use than code energy efficiency. And the owner – client has no idea about this lack of achievement.

If ZEB was incorporated as the energy use goal for the energy audit (ZEB = HERS Index of equal to or less than 30), then the energy audit would include a list of all improvements to the building thermal envelope components and mechanical systems necessary to achieve the performance of HERS Index 30 or less. Those components and systems that can be upgraded for the shortest return on investment can still be done first, the available cash incentives will still be provided, the work for those components will be done to the ZEB level, the owner will know exactly what they can do next when pinched again by the increasing cost of energy, and when all items on the improvement list are completed the building will be performing at a HERS Index of 30 or less, nothing left to do but put the solar collectors on the building to eliminate the purchase of remaining energy uses.

Nationally, the energy audits are slipshod with no energy use goal input from the owners. You get what the auditor decides to give you, driven most often by whatever incentives are being given. The auditor is free to do whatever, because there is no energy use goal that creates the environment to determine what is necessary to achieve the goal. As the purchaser of the audit, the client is given no say and no idea what five different energy auditors are going to propose, nor what that means in the overall picture of the HERS Index. All energy audits that I have had the honor of reviewing represent the way energy audits are done as described above.

Imagine the difference for owner participation and decision making when owners are given the opportunity to request an energy audit that will tell them their building’s HERS Index Now, and what would be required to achieve a HERS Index of 30 or less. This will make the energy audit permanently useful for this building, instead of a slipshod in time. The owner will always know what to do next as the cost of energy goes up. And when they are done with all on the list in one year or ten years, then their building will be performing at ZEB, HERS Index 30 or less.

by John Unger Murphy,  May 17, 2011
GET Aug2011 page 29

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