Grid-connected solar power generation, either dispersed or centralized, has developed and grown at the margin of a core of dispatchable and baseload conventional generation. As the penetration of this variable resource increases, the management of the underlying core gradually becomes more complex and costly.
The challenge ahead for grid-connected solar is to evolve beyond the margin and the context of underlying conventional generation management. Activity 3.5 focuses on this challenge where the transformation of intermittent variable renewable energy (VRE) resources such as solar and wind into firm, effectively dispatchable, power generation resources is a prerequisite to the displacement of the underlying conventional generation core.
Substantiated by in-depth case studies, this report infers that nearly 100% VRE power grids firmly supplying clean power and meeting demand 24/365 are not only possible but would be economically sound if VRE resources are optimally transformed from unconstrained run-of-the weather generation into firm generation. VREs are thus capable of entirely displacing all climate disruptive conventional sources economically (provided now emerging grid-forming inverter technology resolves any grid frequency and stability issues resulting from the displacement of conventional rotating power generation). The variable-to-firm transformation enablers include energy storage, the optimum blending of VREs and other renewable resources, geographic dispersion, and supply/demand flexibility. Most importantly this transformation entails overbuilding and operationally curtailing the VREs ─ a strategy we term applying implicit storage. This strategy ensures acceptable VRE production costs.
This report summarizes ten experts’ contributions focusing on firm power generation at near 100% renewable energy penetration. In addition, four contributions describe ‘entry level’ firm power generation objectives, easier to achieve in the short-term, but using the same enabling strategies, where firmness is defined in terms of meeting forecast VRE production instead of full load.