Technology Status - NET Nowak Energie & Technologie AG

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● increased cell efficiency (a 2% to 4% cell efficiency increase translates into
an efficiency gain of 20% for established crystalline silicon technologies
and up to 40% for thin-film technologies);
● improved manufacturing and handling processes (fewer broken and outof-spec
products, improved material utilisation).
The cost reduction potential is around 25% for a tenfold up-scaling and
another 25% for increased cell efficiency and enhanced processes.
Key findings from various studies indicate:
● cost reduction potential in semiconductor processing must be exploited
to lower manufacturing costs;
● feedstock issues become more important for crystalline silicon once
manufacturing costs have substantially decreased. Thus, availability of
low-cost material must be assured;
● costs for other materials (substrates, encapsulants, pottants, mounts,
electrical connections) dominate when semiconductor costs are optimised;
● overhead costs decrease in relative terms when manufacturing volumes
increase.
Projected costs vary considerably for individual PV cell and module
technologies but have common aspects: R&D and increased volume can
contribute to overall cost reductions of almost 50% within a decade in the
areas of feedstock, device and cell efficiency, and manufacturing processing.
Although modules represent about 60% of grid-connected system costs,
reducing the cost of components BOS is also important for bringing down
total system costs. For instance, the efficiency rate of common inverters in
the range of 1.5-3.3 kW was between 85.5% and 90% in the years 1988 to
1990. Today their efficiency is above 90%, even for smaller units (100-200 W),
and is often close to 95% for the most common models. Technical
improvements are expected to increase efficiency and extend their lifetime to
15 - 20 years. Costs for inverters in particular could be reduced through
higher manufacturing volumes.
Cost reductions have been more substantial for BOS (inverter, mounting
structure, installation labour and planning) than for modules in recent years,
especially in markets that have reached a critical mass in volume sales, such
as residential systems in Japan and Germany. For example, installation costs
are lowest for 2 kW PV installations in Germany thanks to enhanced
standardisation of planning and mounting procedures and materials, as well
as installation experience that has resulted in the need for less on-site labour.
In Japan, PV is becoming a common building material. Many houses are
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