Possible Hurdles Foreseen by a Large-scale Introduction of Renewable Energies

Abstract

This article discusses possible hurdles foreseen by a large-scale introduction of intermittent renewable energies (described as “RE” hereafter) from wind and photo-voltaic (the latter “PV” hereafter) powers. The analysis was carried out using actual recent load, wind and PV data of 15 min resolutions of Kyushu Electric Power Co. The results indicate the following three conclusions: (1) the surplus energy and grid power would become large once the proportion of the annually produced energy by RE would become above 40 % of the total annual electric load, (2) CO₂ emission from back-up systems due to thermal power stations burning fossil fuels did not go down much even by a large amount of RE introduction, and (3) in order to ameliorate this situation and for RE to be implemented of its full potential, an increase of the present pumped storage capacity of Kyushu Electric Power Co. by more than a few tens of times is necessary.