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addresses the notion of the likely market composition, and then proceeds to assess the market size.

Chapter 7 showed respondents were grouped into four tiers of market development. Figure 11 shows that most respondents within the tiers (85%) fall in either Tier 1 or Tier 2. This finding is a function of two facts: (1) the sample as a whole tends to be favorable toward GPV and (2) respondents included in the tiers analysis have indicated likely action (or inaction) consistent with their measured attitudes toward GPV (either for or against using GPV in their own homes). 1

The four tiers originally defined in Table 30 do not encompass all the respondents included in the crosstabulation of the two cluster regimes, as shown in Table 29. The remaining respondents, as already noted, constitute a group for which a clear-cut definition could not be constructed.

Composition of the GPV Market

To obtain the most detailed characterization possible of prospective GPV purchasers, the tiers of individuals developed in the previous chapter were analyzed on the basis of the study’s key demographic variables. This analysis took the form of crosstabulating tier membership against the

Figure 11. Percentages of Respondents in All Tiers Represented by Each Respective

Tier

various demographic variables and performing Chi-square significance tests to assess the comparability of percentage distributions. For some of the variables, no statistically significant differences were found among the tiers. For example, all tiers were determined to be essentially identical on the basis of gender, marital status, size of the community of residence, and principal source of home heating fuel. On the basis of other variables, however, the tiers are considerably diverse, as indicated in Table 31.

Based on the foregoing analysis, it is possible to descriptively name and characterize the four tiers originally identified in Table 30. These descriptions are presented below.

Tier 1: Early Adopters—those who say they will purchase and who will actually do so soon (38%)

Tier 1 homeowners are individuals who say that their purchase of a GPV system is likely or highly likely, assuming affordability, and whose overall attitudes toward GPV

technology suggest they are likely to follow through in the immediate near term. This first tier contains a higher percentage of skilled workers than the other tiers (except for Tier 3), and the lowest percentage of college graduates among all tiers. A higher percentage of its members are Western Slope (Grand Junction and other areas west of the Continental Divide) residents than in other clusters. The dominance of political conservatives is relatively low in Tier 1.

The Early Adopter tier includes both innovators and early adopters. Ordinarily, this tier would be expected to comprise approximately 16% of a population (see Figure 1). But the tier’s population, as a function of the broad favorability toward GPV expressed by survey participants and of the way the analysis was conducted, shows a greater representation of potential GPV adopters than would usually be expected—and greater than in the population of homeowners as a whole.

Tier 2: Mid-term adopters—those who say they will purchase but will wait until a later time (47%) Tier 2 homeowners are individuals who say that their purchase of a GPV system is likely or highly likely, assuming affordability, but whose overall attitudes toward GPV suggest they are likely to wait until the technology has been adopted by the first tier. This second tier contains some of the most affluent, highly educated, and highest job positioned individuals, and it has a high percentage of residents from the Denver/Boulder area. Though still politically conservative, it is less so than Tiers 3 and 4.

Table 31. Selected Demographic Characteristics of Respondents Included in the Tiers Characteristics of Respondents Tier 1 Tier 2 Tier 3 Tier 4 All tiers Statistical Significance*

Percent under the age of 50 62 66 70 48 63 p <.0001

Percent living in Denver/Boulder area 58 71 47 70 64 p <.001 Percent living in Grand Junction or other

Western Slope areas

11 4 11 4 7 p <.001

Percent with a college degree or higher 47 69 58 55 59 p <.0001 Percent with annual incomes of at least

$50,000 63 80 63 67 71 p <.002

Percent employed in professional or managerial positions

51 67 51 43 58 p <.0001

Percent who are retired 14 5 5 28 10 p <.0001

Percent who are skilled workers 14 8 17 4 11 p <.0001

Percent who claim to be conservative or

liberal 42/28 40/31 64/11 69/13 44/27 p <.0001

*In all cases the size of the p-value indicates that there is at least one significant difference among the tiers. Source: Constructed by the authors.

Tier 3: Late adopters—those who say they will purchase, but are the least likely to follow through (8%) Tier 3 homeowners are individuals who say that purchase of a GPV system is likely or highly likely, assuming affordability, but whose overall attitudes toward GPV suggest they may not be motivated enough to follow through with a purchase commitment in the foreseeable future. This third tier contains higher percentages of women, younger residents, married couples with children, and skilled workers than the other tiers. High percentages of its members also say they are politically conservative.

Tier 4: Nonadopters—those who absolutely will not purchase (7%)

Tier 4 homeowners are individuals who say that purchase of a GPV system is unlikely to highly unlikely, either now or in the future. Their overall attitudes toward the technology are negative. This fourth tier contains high percentages of retirees, residents from the Denver/Boulder area, and political conservatives.

The distinctiveness of the individual tiers can be substantiated and validated by crosstabulating tier membership against other variables that were measured as part of the survey but which did not play a direct role in defining the tiers. Two such crosstabulations are shown in Tables 32 and 33.

Table 32 shows the percentages of respondents in each tier who indicate they possess each of five characteristics pertaining to values and lifestyles. As indicated in the table, there are significant differences among the tiers on the basis of all these characteristics. Tier 1 (Early Adopters), for example, is significantly different from the other tiers on the basis of all five characteristics. The members of Tier 1 are more likely to accept lifestyle modifications to help the environment, to buy environmentally friendly products even if they

cost more, to be as independent and self-reliant as possible, to experiment with new ways of doing things, and to view themselves as leaders.

Likewise, Table 33 shows the percentages of respondents in each tier who indicate they possess other characteristics related to adoption of GPV technology. There are also significant differences among the tiers on the basis of all these additional characteristics, indicating the existence of varying attitudes. A significantly higher percentage, for example, of respondents in Tiers 1 (Early Adopters) and 4 (Non-Adopters) indicate they already know enough to decide whether or not to purchase a GPV system. (Presumably, among those indicating they know enough to decide, Tier 1 members already know enough to purchase, while Tier 4 members already know enough not to purchase.) A significantly higher percentage of respondents in Tier 1 indicate they would look for more information about GPV than in other tiers. A significantly lower percentage of those in Tier 4 indicate willingness to pay for a GPV system of any size than in other tiers. Finally, in Tier 1 a significantly higher percentage of respondents are favorable toward various net metering options, while in Tier 4 a significantly lower percentage is not. A higher percentage of Tier 1 respondents, for example, are willing to accept avoided cost for excess electricity and to donate excess electricity to low-income households. Curiously, a majority of Tier 4 respondents (most of whom have no interest in net-metering options) indicate they would prefer retail cost when it comes to selling excess electricity back to the utility grid.

Table 32. Values and Lifestyles Characteristics of Respondents Included in the Tiers Characteristics of Respondents* Tier 1 Tier 2 Tier 3 Tier 4 All Tiers Statistical Significance** Percent who would accept

lifestyle modifications to help the environment

62 57 11 9 52 p < .0001

Percent who would buy

green 58 52 17 13 48 p <.0001

Percent who are self-reliant 80 68 74 50 72 p <.0001

Percent who are innovative 78 65 44 29 65 p < .0001

Percent who are opinion leaders

63 62 55 39 60 p < .002

*Percentage of respondents giving highly positive responses of 9 or 10 (on a 10-point scale) to the associated survey questions.

**In all cases the size of the p-value indicates that there is at least one significant difference among the tiers. Source: Constructed by the authors.

Other characteristics suggested by responses to the survey questions could also be considered. Note that, for purposes of completeness, Appendix E contains a crosstabulation of tier membership against every study variable (survey question).