• A picture of a dwelling's comparative level of energy consumption is produced through an analysis of past energy-consumption data adjusting for building size, climate, and client energy behavior. An investment guideline is then set reflective of the potential for saving energy.

• Analytical tools such as the blower door, manometer, or heating-efficiency test equipment further quantify patterns of energy consumption specific to that structure. (All subgrantees in New York State are required to use blower doors.)

• A diagnostic reasoning approach is then used to figure out the dynamics of that consumption. An appropriate workscope is developed to produce an optimum level of energy savings for the investment level available under DOE rules.

• Most importantly, TIPS systematically incorporates a series of protocols to protect the health and safety of the occupants, using a whole-house systems approach.

   

The study's most important finding was the obvious relationship between pre-weatherization fuel consumption and potential energy savings. When project contractor Synertech Systems Corporation organized the data in terms of historical fuel use (from relatively low use to relatively high use), there was a correlation between the initial level of fuel usage and the level of actual savings.

This finding called into question the conventional wisdom of the time--that each eligible client should receive about the same benefit, so each unit should receive similar amounts of services, and therefore funds. The fact that most energy conservation programs budgeted expenditures on a per-household basis forced us to confront the fact that we regularly spent too much in some homes and too little in others (see Table 1).

To properly characterize a building, it is first necessary to know its energy efficiency as compared to similar buildings. To do that, we determined the mean pre-weatherization energy factor (in Btu/ft2/heating-degree days) for 5,000 New York single-family dwellings (15.1 on initial analysis). We divided the mean usage of 15.1 into the average funds available per unit (the $1,600 cost per unit mandated at the time) to set an economic investment guideline for each Btu/ft2/HDD. We set this investment factor at $100 for single-family dwellings.

The data used to characterize a building in terms of the relative size of its energy problems are critical in identifying where the problems lie. The relative importance of convective, conductive, and mechanical heating problems in a structure's overall energy performance emerged from the TIPS investment process. Within the framework of the unit investment level, workscope choices and implementation are intertwined. The TIPS decision tree illustrates how empirical data must interact with other information (see Figure 1).

Some of the major differences between traditional and TIPS weatherization workscopes are:

• Health and safety tests are performed first, with any necessary actions taken prior to energy work.

• Blower-door protocols require initial, interim, and final tests to track air infiltration reductions.

• Problems with heating distribution systems are diagnosed and treated more than in the past.

• High-density, blown cellulose is used when possible to address conductive and convective energy losses simultaneously, which sometimes makes it unnecessary to do further sealing.

• Energy education is geared to the client's specific circumstances.

Increasing Cost-Effectiveness

All 60 New York weatherization agencies have been trained to use TIPS. Table 2 reflects actual fuel-usage analyses of more than 180 units weatherized by 17 local weatherization agencies throughout the state. Clearly, the investment strategy has worked, significantly increasing cost-effectiveness. Savings that would have been deemed unattainable several years ago are now regularly achieved.

To appreciate the success of TIPS, one need only compare the average first-year energy savings per household to the recently released results of the National Weatherization Evaluation (see Weatherization: The Single Family Study, HE Sept/Oct '93, p.11). TIPS generated first-year savings of 45.5 MMBtu per household--almost three times the national average of 17.6 and about 2.5 times the national average for cold and moderate regions (19.0 and 18.2 respectively).

The program requires the practitioner to pay attention to detail and recognize that the energy-use problems for each house may be like fingerprints, unique, requiring the examination of the data specific to each house. According to Larry Harmon, who tested TIPS as a New York subgrantee and is now Vermont's WAP director, TIPS has actually produced goose bumps when experienced users discover they are achieving 50% documented savings using it.

Although TIPS uses computerized software, it is much more than an audit tool. The software can be used separately, but individuals with a copy of the software must understand that TIPS was never intended to be a black box. TIPS is based on the contention that, given the right tools and information, the human brain will outperform even the most sophisticated computerized energy audit program.

-- Rick Gerardi and Pat Sweeney Rick Gerardi is Director and Pat Sweeney is Assistant Director of the New York Department of State's Weatherization Division which resides within the Division of Economic Opportunity.

Figure 1. The TIPS Decision Tree.

1991-1993 Consumption Groupings and Cost/Benefit Results TIPS Weatherization

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