TwinPeak Technology Whitepaper
NEW MODULE
What is the REC TwinPeak Series?
The REC TwinPeak Series is a new solar panel with an innovative
layout and different cell technology that increases the power available
from a polysilicon cell up to Wp. In combination, the technology
inherent in the new REC TwinPeak Series delivers an increase of Wp
per panel compared to REC’s current REC Peak Eenrgy Series panel.
The most obvious difference in the REC TwinPeak Series compared
to a standard solar panel is the cell design. The new panel is based
on standard sized cells of x mm that have been cut into two
equally sized pieces ( x mm), to give half-cut cells.
The panel is then split into two ‘twin’ sections of cells each,
connected in series, in three strings. The two sections are then
connected in parallel in the center to give a panel of cells (fig. ).
This new design and layout is supplemented by a collection of other
enablers:
• PERC (Passivated Emier Rear Cell, also known as Backside
Passivation)
• Four bus bars
• Split junction box design
For which markets is the new panel suitable?
The higher power and efficiency afforded by the new panel means
customers will be able to boost their overall energy yield from the
same surface area; this makes the REC TwinPeak Series ideal for the
residential and C&I markets where rooop space is oen limited.
The increase in power per m allows customers to generate the most
energy out of their installation reducing the balance of system costs
for installers and system owners and ensuring solar energy remains
cost-efficient.
What advantages do half-cut cells offer?
As mentioned above, a half-cut cell is a standard cell that has been
split into two equal pieces to produce smaller cells (fig. . Through
this, the current per cell is also reduced by half. With the reduction in
current, comes a reduction in power loss internal to the cell. Power
loss is generally proportional to the square of the current, therefore
power loss in the complete REC TwinPeak Series panel is reduced by
a factor of four (
Ploss
= R
.
I
, where
R
is the resistance and
I
is the
current).
The reduced loss of power in a half-cut cells produces a higher fill
factor and higher cell efficiencies resulting in beer energy yields,
especially at times of high irradiance. Panels with a higher fill factor
have a lower series resistance meaning reduced loss of current
internally in the cell.
Additionally, the new layout improves the performance of the
TwinPeak design in reduced irradiance conditions compared to
a standard panel. For example, if a standard panel is installed in
portrait orientation and the boom is shaded, the power output of the
complete panel is zero, due to the bypass diodes closing the internal
strings. The layout of the REC TwinPeak Series ensures that in the
same conditions, due to the separate twin sections, the power output
is at least fig. .
The improvements made in the reduction of resistance through half
cut cells add an overall around Wp per panel extra power output.
The new REC TwinPeak Series:
The combination of different technologies maximizes the power from a
polycristalline platform and optimizes long term panel performance
The REC TwinPeak Series is a brand new solar panel development that features innovative design with
high panel efficiency, i.e., higher wa classes. Based on a polysilicon platform, the REC TwinPeak Series
encompasses a number of new and innovative technologies that ensure the panel can compete strongly with
mono p-type and n-type products on the market.
Fig : Front and rear view of the REC TwinPeak Series solar panel, showing the twin section
design enabled by the half-cut cell layout, bus bar cells and split junction box on the rear
Current rejoins
and flows out
of the panel
Fig : Flow of electricity in the REC TwinPeak Series. The two twin sections reduce
internal resistance and ensure continued production of energy when partially shaded.
Current flow
into the panel
Current splits to
flow around the two
halves of the panel
Fig : A half-cut cell showing the bus bar cell design