There is no universal scale that you could use to measure attitudes towards energy conservation. In your survey instrument, you could use a qualitative scale such as Low, Medium, or High. Alternatively, you could use a numerical scale such as 1 (for Low), 2 (for Medium), and 3 (for High).

What is more important and needs to be defined is the following:

1) What population sample size you will use in order to obtain statistically significant results?

2) What research method you plan to use? For example, qualitative, quantitative, or semi-quantitative methods.

Hope this helps answer your question.