  This paper presents a techno-economic optimization model to analyze the
economic viability of a PV-battery system for different customer groups in
Switzerland clustered based on their annual electricity consumption, rooftop
size, annual irradiation and location. The simulations for a static investment
model are carried out for years 2020-2050 and a comprehensive sensitivity
analysis is conducted to investigate the impacts of individual parameters such
as costs, load profiles, electricity prices and tariffs, etc. Results show that
while combining PV with batteries already results in better net present values
than PV alone for some customer groups today, the payback periods fluctuate
between 2020 and 2035 due to the mixed effects of policy changes, costs and
electricity price developments. The optimal PV and battery sizes increase over
time and in 2050 the PV investment is mostly limited by the rooftop size. The
economic viability of PV-battery system investments varies between different
customer groups and the most attractive investment (i.e., that has the shortest
payback period) is mostly accessible to customer groups with higher annual
irradiation and electricity demand. In addition, investment decisions are
highly sensitive to payback periods, future costs, electricity prices and
tariff developments. Lastly, the grid impact of the PV-battery system
deployments are investigated by analyzing the residual Swiss system load
profiles. The dynamics of residual load profiles caused by the seasonal, daily
and hourly patterns of the solar generation emphasizes the need for flexible
resources with fast ramping capabilities.
