Electricity + Control October 2015

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ENERGY + ENVIROFICIENCY
power will doubtless have increased many times. It is these future
differences in the cost of energy between the utility costs and the
fixed solar PV cost that should be recognised as part of the long-term
sustainability of owning such an asset. Additionally, in most cases the
asset is attached to a building and would result in improved valuation
of the building. Not only does this have a positive financial implica-
tion, it also has an environmental implication, especially when one
considers the Carbon Tax that will be levied as of 2016. The only way
to negate the carbon tax is to either recycle or produce ‘Green kWh’
from a renewable source like solar PV.
Solar PV loans
In order to drive adoption of solar PV solutions, it is necessary for
financial institutions to recognise their value and assist businesses
and homeowners with funding these systems. Forward-thinking fi-
nancial institutions should look to leverage the security of a loan for
solar PV power against the asset itself, as it will pay for itself many
times over in years to come. The asset could also be recognised as
part of the building itself and be financed utilising an extension of
the building bond. In addition, government needs to come on board
by assisting financial institutions with tax rebates for their efforts in
financing Solar PV systems. This is sound strategy, as by funding
these systems, financial institutions are contributing to the overall
reduction in carbon output and, more importantly, helping to resolv-
ing the country’s current energy shortages.
Connecting to utility
In addition to funding, connecting to the utility remains a challenge.
One of the most pressing issues is the nature of pure solar solutions
(without energy storage capability), in that they are only able to produce
energy during daylight hours, and the energymust be used or dumped.
For the majority of residential applications where nobody is at home
during the day, this generated power will be wasted if a solution to feed
this power back into the grid cannot be resolved. Connection codes
therefore need to be finalised, and metering for two-way energy flow
needs to be implemented. It is also important to find a solution to the
problem of optimising the use of all renewable energy generated to
the advantage of both the end-user and the utility providers.
Net metering
The concept of net metering, whereby users sell their excess renew-
able energy back to the utility for credit and utilise these credits
when the renewable source experiences shortfall (such as at night
when there is no sun to power solar PV systems) is one that has
great potential to benefit all parties concerned. For most residential
applications, this form of energy trading works well. Some utilities
may limit the amount of energy you can sell back for credits to the
amount of utility energy used (i.e. if you use 2 000 kWh per month,
than you may only sell back a maximum of 2 000 kWh per month).
Another systemwould be to annualise this amount, enabling owners
tomake better use of the credits throughout the year, such as in winter
where generation may not match overall consumption.
Feed-in tariffs
Theoretically, users could manage consumption and generation of
energy to a zero balance and not have to spend a cent on energy from
the utility for the year. This idea in principle is appealing, particularly
for consumers and business, however for utilities this could cause
problems. If renewable energy customers are not paying what they
used to pay for electricity, but rather supplementing their own power
generation with utility power, how does the utility find revenue to pay
for the maintenance of the generation, transmission and distribution
network the entire systemuses? Feed in tariffs have been suggested as
one solution to this problem, whereby the utility purchases the excess
energy from providers, while users still purchase utility power, and
there is no obligation to consume at the same rate as you sell energy.
Conclusion
Regardless of the challenges involved, solar PV remains the most
viable and cost effective alternate energy source for South Africa, a
country that experiences significant hours of sunshine for much of
the year in the majority of its regions. If these problems can be sat-
isfactorily resolved and solar becomes a mainstream power genera-
tion source, not just for the utility but for business and homeowners
too, the currently bleak power prospects of South Africa may have a
brighter future after all.
take note
Enquiries: Email or
Kevin Norris is the
consulting solu-
tions architect for
Jasco Renewable
Solutions.
Dave Smith is the
managing director
of Jasco Renewable
Energy.
• PV plants are costly and Return on Investment is slow.
• The many issues relating to the connection of solar plants
to the main grid have slowed the uptake of these solutions.
• Addressing these challenges is key to harnessing the
power of the sun as an alternate, sustainable energy
source.
43 October ‘15 Electricity+Control