Delta-T Devices SPN1 Sunshine Pyranometer for PV Applications

Burwell, UK (ots) - Photovoltaic developers and triallists find
the SPN1 Sunshine Pyranometer a valuable tool for research and for
performance validation. When making PV investments, it is essential
to identify the best sites. An SPN1 can be used to quantify the
available global and diffuse radiation at potential sites. Later,
after an installation has been completed and power is being
generated, the SPN1 can help to monitor the short and long term
efficiency of the panels, and these results can be fed back into
improved PV panel design.

The key advantage of the Sunshine Pyranometer type SPN1 is that
it measures global (total) and diffuse radiation, and sunshine
state - all in one instrument. It is also easy to use and needs no
routine adjustment or polar alignment. Output from an SPN1
Sunshine Pyranometer allows calculation of DNI (Direct-Normal
Irradiance) in sun tracking, horizontal and tilted installations.
It is a common practice to compare solar panel efficiency to DNI,
particularly in solar energy field trials.

The SPN1 is a meteorological class instrument designed for long-
term outdoor exposure, and is an affordable and effective
alternative to traditional shade-ring pyranometers, the Campbell-
Stokes and other sunshine recorders. It also provides some of the
functionality of expensive pyrheliometers.

- Global (total) and diffuse horizontal irradiance in W.m -2

- DNI (Direct-Normal Irradiance) calculation

- Sunshine threshold to WMO definition: >120 W.m -2 in the direct
beam

- No moving parts, no shade rings, no motorised tracking needed

- No routine adjustment or polar alignment needed

- Works at any latitude

The unique design of the SPN1 Sunshine Pyranometer uses a
patented array of thermopile sensors and a computer-generated
shading pattern to measure the direct and diffuse components of
incident solar radiation. The shading pattern and thermopiles are
arranged so that at least one thermopile is always fully exposed
to the solar beam, and at least one is fully shaded from it,
regardless of the position of the sun in the sky. A microprocessor
derives the global and diffuse radiation values, which allows an
estimate of the direct beam, and hence sunshine hours, to be
calculated. The SPN1 Sunshine Pyranometer is protected by patents EP
1012633 & US 6417500.

The Sunshine Pyranometer provides 2 voltage outputs for global
and diffuse energy, and a digital output of sunshine state for
data logging. Delta-T Devices' reliable low cost logging solution
for the SPN1 is the GP1 Data Logger.

The SPN1 has a precision ground glass dome and uses wideband
thermopile sensors; it achieves a near ideal spectral and cosine
response. The internal heater keeps the Sunshine Pyranometer clear of
dew, ice and snow down to -20°C, ensuring reliable readings in
difficult climatic conditions.

In summary, the SPN1 Sunshine Pyranometer is a high performance
instrument offering a unique combination of solar radiation
measurements in a single, rugged, low maintenance device, making
it ideal for PV applications.

The SPN1 will be on display at the Delta-T Devices Intersolar
stand - No. B2.483.

Notes to Editors:

About Delta-T Devices:

(Intersolar stand No. B2.483)

Established in 1971, Cambridge based Delta-T Devices specialises
in instruments for environmental science, with a strong focus on
solar energy studies and environmental monitoring. Their uniquely
designed and patented SPN1 Sunshine Pyranometer and BF5 Sunshine
Sensor provide innovative measurement solutions for a range of
photovoltaic related applications. Delta-T Devices takes pride in
operating at the cutting edge of the environmental technology
arena, and maintaining the strong customer-oriented focus that has
always been central to its philosophy.

For further information please contact:
sales@delta-t.co.uk
+44 (0)1638 742922

Delta-T Devices Ltd
128 Low Road, Burwell, Cambridge, CB5 0EJ, UK

Tel: +44 1638 742922,
Fax: +44 1638 743155,
E-mail: sales@delta-t.co.uk,
Web: www.delta-t.co.uk