Barros, Carlos Pestana; Gil-Alana, Luis A.; Payne, James E. - In: Energy Economics 40 (2013) C, pp. 425-432
, geothermal, solar, wind, wood, waste, and biofuels) using innovative fractional integration and autoregressive models with … biofuels the estimates of fractional integration are higher than 0.5 but less than 1.0 implying nonstationary, but mean … reverting behavior. In the case of geothermal and waste the estimates of fractional integration are around 0.5 and in the …