Cost-efficiency potential of solar energy on a global scale: Case
studies for Si solar modules with PERC and heterojunction structures
Abstract
Levelized cost of electricity (LCOE) is a crucial metric for assessing
the socio-economic cost-efficiency potential of various energy sources
including solar photovoltaics. Nevertheless, accurate LCOE estimations
for commercialized high-efficiency Si solar modules with passivated
emitter and rear cell (PERC) and silicon heterojunction (SHJ) structures
have been lacking. In this study, we present the first global LCOE
estimates for a PERC module (20% cell efficiency) and a SHJ module
(23% cell efficiency), which have been derived by (i) performing
rigorous energy-yield calculations with full-spectral and
temperature-dependent simulations that incorporate all essential
meteorological effects and (ii) considering country-specific capital
costs and discount rates. Moreover, to determine the universal global
LCOE, the LCOEs for three distinct installation capacities (100 MW for a
utility, 500 kW for a commercial, and 5 kW for a residential system)
have been unified by selecting an appropriate system size at each
location based on a population density. We find that the LCOEs of both
PERC and SHJ systems are below 3 cent/kWh in 2020 US dollar in many
areas of China, Saudi Arabia, the United States, Australia, Chile, and
Botswana where the conditions of a high energy yield, low population
density, low capital cost, and low country-risk premium are satisfied
simultaneously. In contrast, many European countries exhibit a moderate
LCOE of 3~5 cent/kWh. Notably, Japan and Russia exhibit
quite high LCOEs (6~10 cent/kWh) primarily due to
significantly higher installation costs and moderate energy yields.
Importantly, the global LCOEs of the PERC and SHJ modules are quite
similar, with the SHJ module showing a slightly better cost performance
in the regions near equator due to its low temperature coefficient.
Conversely, the PERC module demonstrates cost advantage in the northern
hemisphere due to a lower module cost.