The last chapter of the book presents first what is known as hierarchical forecasting, which is a spatial forecasting framework suitable for grid integration. Power grids are in hierarchical forms, in that, the power generation by each photovoltaic module sums up to the power generation of the plant, generation by each plant connected to a distribution node adds up to the nodal generation, and distribution nodes are connected to a transmission bus. In view of this hierarchical structure, forecasts are needed on each level of the hierarchy, and these forecasts should be aggregate consistent, as to facilitate operations management of the grid as a whole. This chapter outlines hierarchical reconciliation methods for both deterministic and probabilistic solar forecasts. The second half of the chapter revolves around a novel concept called firm power delivery, which is able to eliminate entirely the uncertainty in solar forecasts or solar power generation, and thereby making solar power dispatchable. In short, a firm photovoltaic plant is able to meet demand on a 24/365 basis, with the help of firm power enablers, such as electric storage, geographical smoothing, demand response, or overbuilding & proactive curtailment. The underlying problem is to strategically configure and operate a mix of firm power enables, such that the overall cost-effectiveness is optimized.