Sammendrag
The elimination of the so-called solar-tax in Spain at the end of 2018, which
had earlier made investment in residential PV systems unattractive, has opened
a new horizon for self-consumption and thereby providing an opportunity for
households to reduce energy costs. This thesis presents an investment analysis
to determine the optimal size of a grid-connected energy storage/PV system that
minimizes the electricity bill in Spanish households. The problem is formulated
as a linear programming optimization and implemented in Python. The study
considers two models, one stochastic and one deterministic, which perform annual
simulations for three households with different annual load consumption
patterns. Real data from solar radiation, spot prices and load consumption are
provided for the modelling. Results show that it is more cost-effective to invest
in PV systems rather than in battery storage and up to 23% reduction in the
annual electricity costs can be achieved in the best case scenario. Moreover, a
sensitivity analysis on energy storage prices is carried out, which mainly affects
households with high energy consumption.
