Consumers'' adoption deals with consumers'' behavior to adopt innovations including the steps in the decision to purchase or reject a new product (technology): 1) Pre-existing problem or need 2) awareness 3) interest 4) pre purchase (pre trial) evaluation 5) trial and 6) adoption (or rejection) 7) post adoption or post purchase evaluation. These are studied by consulting literature of the model of consumers'' adoption process which is a process of the diffusion of innovations consisting of stages through which a consumer passes while arriving at a decision to purchase or reject new products such as sustainable energy technologies. Rejection of a new product indicates low product introduction rate due to failure of new product attributes to meet consumers'' expectations. That means, the new product attributes fail to meet consumers'' needs and wants. When there is a gap between consumers'' expectation and consumers'' actually perceived product attributes, this leads to image (brand) problem.Thus, understanding how individuals make decisions in order to fulfil their needs and wants is important for researchers and intervention designers concerning impact of human behaviour on energy use.