users will have to cope with this situation by choosing one of the conflicting sources; by using political pressure to obtain information they can trust; by creating institutions that will provide the information they want; by rejecting all the expert advice and relying on nonexperts; or by doing nothing.
We have pointed out that since energy users cannot get accurate information about the ultimate comparative cost of different energy options, they will rely on the most credible available information. In fact, there is a large body of well-controlled experimental literature showing that the effectiveness of a given message depends on the credibility of the source of the message (Hovland, Janis, and Kelley, 1953; McGuire, 1969, 1983). Credibility involves a combination of expertise in the content of the message and trustworthiness. Other things being equal, the greater the expertise and trustworthiness of the communicator, the greater the impact on the audience. A given message, when attributed to a person of high credibility, produces greater attitude change in the target audience than the identical message when attributed to a person who is generally regarded as either inexpert or untrustworthy (Hovland and Weiss, 1951; Aronson and Golden, 1962; Aronson, Turner, and Carlsmith, 1963).
Many of the sources offering energy information to households are considered by the public to be expert, so in this sense, they are equally likely to be effective. When the experts disagree, however, users are most likely to rely on the sources they trust. Trust in sources of energy information does seem to make a difference.
There is some anecdotal evidence on the trust issue drawn from the experiences of community-based programs that offer energy conservation services for households. In low-income communities, both in cities and rural areas, grass-roots energy groups have gained the trust of residents because of their personal contact with the community, where more formal institutions might well have been ignored (Stern et al., 1981). But more convincing evidence comes from experimental research. In one study that has experimentally investigated the source of energy information, Craig and McCann (1978) sent a pamphlet describing how to save energy in home air conditioning to 1,000 households in metropolitan New York. Half the households received the information in a mailing from the local electric utility, the other half in a mailing from the state regulatory agency for utilities. The following month, households that had received pamphlets from the regulatory agency used about 8 percent less electricity than households that had received the identical pamphlets from the local electric utility company. Since air conditioning accounts for only part of each household’s use of electricity, the 8 percent savings is clearly an under-