THURSDAY 21 JUNE, 2012 |
Myth Busting: Winter And Solar Power
With winter solstice - the shortest day of the year - upon us, it's an appropriate time to bust
another myth about rooftop solar panels.
While today may be the shortest day, owners of rooftop solar power systems
aren't necessarily shaking their fists at the sky, gnashing their teeth and
rending their garments. Winter is still a good time for solar electricity
A popular misconception is that solar panels work best on the hottest days. This
simply isn't true - in fact it's quite the opposite. Heat is the enemy of solar
panels; it's just that during summer the days are far longer which more than
makes up for the impact.
, not all solar
are created equal and it's the impact of heat that is one of the
critical aspects that sets brands apart. An important module specification is
called "temperature coefficient". If the temperature coefficient
rating of a panel is -0.46%, this means for each degree over standard testing conditions
(STC - 25 degrees Celsius) the module's output is reduced by -0.46%.
Cooler weather is the friend of solar as panels become more efficient in turning
the sun's rays into electricity. A blue-sky winter's day can see some amazing
levels of power produced on an hourly basis compared with summer.
Where winter does have a marked impact on production is in relation to cloud
cover and shorter sun-hours - and this does drag down overall electricity output
compared to the summer months.
To illustrate the differences throughout the year; here's a look at the average
annual solar irradiation levels in Melbourne and Sydney:
Melbourne may not be renowned for clear sunny days during winter, but as the
above graph shows, Melbourne certainly experiences enough sunlight to make solar
panels more than viable.
To determine solar radiation resources in your area throughout the year, try Energy
Matters' solar quotes
tool, which will generate estimated electricity production per
month, year, carbon emissions reductions and financial benefit information based
on your location and the size of the system you select.
For solar power system owners, a clear sky on a winter's day - however cold or
short it may be - warms their hearts and lines their pockets through electricity
; plus takes off the chill associated with the prospect of
continually increasing electricity prices.
Many Solar Panels Will I Need
Choosing Solar Panels
Other news for Thursday 21 June, 2012
Return to main renewable energy news section
Other Energy Matters News Services