In NY, HPwES is in serious risk of collapse.  While short term triage "solutions" seem de rigueur, vision for sustainable long term cures, and understanding that masking the illness only allows it to spread, appears to be absent.  

Rick Gerardi - one of the father's of HPwES in NY, writes about the next critically important tool necessary for our industry regain credibility and move forward into the 21st century.  Hopefully he can have some of the influence from the outside that he had when he was on the inside.  


In order for residential Energy Efficiency (EE) to move out of the programmatic realm of utility and government strictures and into a true market environment, there arises a need to codify the value of the presumed results of the work: those benefits stemming from the actual energy savings… not deemed savings, not modeled savings; actual monitored savings. We will count only what we can measure.  For the purposes of this discussion we will deal only with the articulation of direct attendant benefits of actual energy savings, fully well realizing that numerous additional but hard to quantify benefits like increased comfort, healthier air quality, and a safer more durable structure also accrue to the end user.  

To read the rest follow this Link to the essay.

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Frist, for the 95% of us who do not live in NY, you might want to explain what "HPwES" is.

Second, this is one of the most lively and sometimes divisive debates in the industry - to measure house performance in a sufficiently uniform manner to allow comparisons, or to measure actual energy use of the occupied home.

My position has always been the same: comparisons and ratings of houses require measurement of the envelope and mechanical systems in the context of the local climate, through sufficiently well-tested and refined energy modelling tools. Otherwise, we're measuring occupant behavior as much as envelope characteristics, and that's far too variable a measure to be meaningful in terms of ratings or comparisons. The same house can appear efficient with one set of occupants and inefficient with another, and the behavior of the same occupants can change over time.

The latter approach is useful to determine occupant response to energy-efficient construction (and whether it follows Jevons Paradox that increased efficiency results in increased usage), and to create educational tools to help change such behavior. But it's not useful as a measure of the efficiency of a house system.

Good point Robert.  

NY HPwES is a state program, primarily funded via SBC/RPS surcharges on gas and electric bills, whereby NYSERDA - a "public benefit" corporation assists homeowners in improving their energy efficiency.  BPI Certification and Accreditation is required for contractors to participate.  Incentives are paid to both contractors and homeowners for their participation in taking the comprehensive approach.  

Robert, I've heard the same platitudes from a lot of people about behavior, occupancy, jevons paradox, etc.  I feel these are excuses in preparation for defending failure.  Do you suspect your promises don't deliver?  

Have you tracked results?  Have you compared them to the results you promised?  Typically I hear those comments from people who haven't.  (In fact, very few contractors ever track, so if you DO you are almost as rare as a Unicorn.)  

I have tracked results.  Behavior and occupancy are the two greatest overblown myths around energy consumption I can think of.  People think the savings will send their children to college, when in fact most would be lucky if it buys them a cup of coffee once a month.  In the rare occasion behavior has large impact, something is really out of balance with the home.  (Most notably, I discovered an improperly installed HRV that caused the homeowner to keep the master bedroom window open 24/7/365.  The bedroom is now comfortable, and I expect next year's consumption will be 1/2 last years.  It's been my experience that improper operation on that scale is rare, and the savings opportunity from correcting it not nearly so great.  Ironically, this was a 3 year old 2500 sf super insulated NYSERDA test case house with sub 800 blower door!) 

Calling a rational - and well-founded - argument "platitudes" and "excuses" demonstrates that you're not interested in an honest discussion but only in asserting that you're right and everyone else is wrong.

Yes I've tracked my homes for 20 years and, because the homeowners were heavily involved and invested in the energy-efficiency of their homes, they have operated almost exactly as my own spreadsheets have predicted (and far below what the HERS rating predicts).

We can control what we build. We can try to influence the way occupants live in the house but ultimately have no control over their behavior (nor should we). If someone likes sleeping in the winter with their bedroom window open, they're going to do that regardless of what the "owners manual" says. If a family has lots of kids who are running in and out all winter, sometimes forgetting to close the door and never turning off lights or appliances, then that's going to impact energy consumption. There are literally an infinite number of occupant behaviors that will effect energy use, even though the house remains as well-built and efficient as it was designed to be.


Sorry, I don't think your arguments are either rational or well founded.  

Your experience is in super high efficiency new build.  I'm sure you have tremendous knowledge around that field to offer, and I'd never attempt to go head to head with you on that, but go back to your earlier comments which are built around parroting dogma that you've heard and believed all your life and apparently no experience taking a crappy home, projecting savings, fixing it, and seeing how your projections fared, and I don't see any leg to stand on in your reply.   

Leaving windows open starts out a comfort issue (IAQ or other), if it turns into a mindless habit that is not correctable, some people can't be fixed.   I always try to fix that, it's a stupid behavior.  Most people don't want to do stupid wasteful things that cost them money.  But they do want and need fresh air.  

Door openings, ok, tell me how much that uses?   Do you blame high consumption of your super-efficient houses on kids running in and out?  If you track, then you have an idea what that costs - $100 a year?  $50?  Sorry, I don't think that's a significant OR avoidable amount of energy.  

Generalizations, like claiming "the sky is falling" or that "behavior can save a lot" are meaningless platitudes.  They are the exact reason EE is failing.  People want to know what they can save, and what it will cost.  

Telling them "a lot" is not the answer they are looking for. 

Thank you for proving my point: you're not interested in an honest discussion.

I think Robert makes a good point here. Energy use is not always indicative of the structure. Certainly occupant behavior can have a huge influence. You can have the best built home with all the bells and whistles that performs well on all fronts. That same house could have grandma with a space heater running 24/7 as she is just always cold. This is not and as Robert pointed out should not be regulated, if MeMe wants a space heater on she should be able to put the space heater on. That one appliance could indicate the contractor did a poor job in his implementation of modern equipment and industry best standards. The home could be fixed but the occupant behavior will not indicate that.

You also make a good point as those savings should be measurable in KwH and good jobs should stand out and for the most part probably will. After most people that invest in a concept normally want to prove it right and not wrong.

It is difficult to put a one size fits all with the metric of occupant behavior. Even more difficult is to lend money based on savings that are not monitored nor proven within accepted parameters. 

Certainly occupant behavior can have a huge influence.

Glen, people say "huge" all the time.  I associate it with the guy selling Kia's on TV...  Buy from him because "the savings are HUUUUU-GA!!!"  

I don't like huge.  I don't think it has a place in what we are trying to accomplish; creating measurement with meaning.  What is huge?  I don't know what huge is, so it's pretty hard to call it wrong.    In huge, do you focus on outliers, or just consider the meat of the curve? Is it 1-5% variance with 90% st deviation, or 30-40% cherry picking outliers to prove your case?

I also feel blaming "behavior" is a cop out.  A scapegoat used to avoid accountability for mediocre work at some level.  I've seen behavior like you mentioned, but it's an outlier, not impediment to accurate modelling (and thus realization), and a knowable input if you do a good job with your interview.  

Furthermore, homes don't exist in vacuums.  In your example the contractor DID fail.  Part of their job is to ask questions about operation, comfort, and to educate, and this behavior indicates they didn't do their job.  One way or the other, grannies space heater should have made the model. 

I make an agreement with my customers that they live in comfort.  This squeezes out risk of crazy behavior.  Modern systems optimize efficiency when they don't sense occupant interface.  When they do, all efficiency bets are off - deliver heat or cooling at all cost (If the installer gets a complaint call they'll change manufacturers).   

Stupid behavior can't always be cured, but you don't get to have the cake and eat it too.  If you can't cure the stupid behavior you don't get to claim the savings, then later blame "behavior" for your inability to model accurately.

My models have very accurately predicted which is why I believe this is not the insurmountable problem so many claim it is.  When you take time to do thorough diagnostics which includes detailed behavioral questionnaire, thorough design which includes aggressively downsizing equipment, and thorough implementation which means tracking savings so you can continuously improve accuracy, realization without crazy scatter is achievable.   

To quote Micheal Blasnik in an interview about why modeling fails:  "...The main culprit, Blasnik said, is not the takeback (or rebound) effect. Citing data from researchers who looked into the question, Blasnik noted, “People don’t turn up the thermostat after weatherization work. References to the takeback effect are mostly attempts to scapegoat the occupants for the energy model deficiencies.”

(I disagree with orientation of some of his conclusions: “Models and auditors underestimate the efficiency of existing heating equipment,” said Blasnik. “They often assume 60% efficiency for old furnaces.” I think the other side, assumption that the new grossly over sized furnace can deliver 95%, and that the ECM at .8 static will save electricity, is the modelling problem here.  But the basic premise that its poor modeling, not occupants going haywire, that is barrier to predictive accuracy.

I've seen 85% efficient furnaces replaced with 95% efficient furnaces where savings were nearly double predicted.  In attempting to understand why I interviewed the homeowner.  The variable - "this house is so much more comfortable, so much more of the time, even with all these windows I find myself adjusting the thermostat once a week instead of 4 times a day." )

I think modeling is a poor metric. I would think actual savings based on past use vs current use is a much more viable figure. The modeling I use does a good job for what it was intended to do but is no crystal ball. Often modeling and the reality are much different. 

Things can change after the interview and retrofit. MeMe decides she wants to live with you instead of Aunt Sally. Empty nester finds child back home after dropping out of college to be a full time gamer etc

I get what you are saying and agree in most cases people invest to see results and they should be the advocate moving forward.

My point is the house might be fixed and the results don't show. This can happen due occupant behavior. I am not say every job would show this but could be problematic as each home is tracked. I am not saying to throw tracking data out of the equation I am simply pointing out a potential inefficiency that should be acknowledged.

your mileage might vary

 I would think actual savings based on past use vs current use is a much more viable figure.

AWESOME!  And now we've come full circle and I refer back to Rick's paper.  


I will have to read more than once. Mr Gerardi professes the simplicity but I was a bit confused with some of the flowery  terms. Some concepts were presented but not explained.

There are a couple of points that stood out

Carbon Credits and Incentives for contractors based on performance.

I will have to read a few more times to form an opinion but on the surface it looks to be a good start point for conversation

Yeah, its early and I think will probably evolve, so questions and recommendations for improvement are probably welcome.

I think the vision is there will be markets for credits aka srec's. Energy reduction, co2, peak load, eventually there may be all kinds of markets willing to pay incentive for bundled verified reductions.

I'm still learning about these guys perspective on the different ways HP can be brought to capital markets. One things certain, without energy data you won't be seeing finance companies participating based upon "freed" cash flows.

Sure, "what you don't measure you can't manage", but also what you don't measure you can't sell.

It seems to me that Gerardi's position is an argument that, in the real world, will lead to a level of regulation and reporting that hampers the operation of small businesses while favoring larger corporations who can afford to dedicate personnel to single tasks, and who can drive an agenda in the industry.

How many homeowners would prefer to work with a company who will send a salesman first, then a $12.00/hr guy to test the house, then a salesman again versus dealing with a small business owner directly from the start?

There are plenty of checks in place within the marketplace to weed out those who are incompetent or corrupt. Including the savvy nature of today's consumer.   


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