Greenparkview public meeting, Tuesday March 8th, 2011
agenda
• Introduction Steve Lenehan, Chairperson, PRA
• Turning Parkview Green Indra de Lanerolle, Greenparkview
• Costs and benefits Rob Brine, Greenparkview
• equipment options Rob Brine, Greenparkview
• What next? Indra de Lanerolle, Greenparkview
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From Red to Green
SafeParkview now has over 500 members - nearly half
the households in the suburb are now contributing to
make Parkview safer.
Our goal now is to see how we can build on that
success to make Parkview greener
Using the power of neighbours and
neighbourhoods
•Harness collective buying power
•Share research and information
•Get the most appropriate solutions at the best prices.
Starting with research
So far we have conducted a survey to gauge interest in
solar water heating
A team led by Rob Brine has also done extensive
research on suppliers, on costs and benefits of solar
water heating and on the technology choices available.
Survey results
•Sent to 700 email addresses at about 480 safeparkview and PRA households.
•195 responses
•55% said they were willing to participate in a bulk solar water heating project
•Average household spends R1,500 per month on electricity
COSTS AND BENEFITS
COSTS AND BENEFITS
Financing a solar water heating system should be viewed in the
context electricity tariff hikes and electricity shortages.
R1000 bill now will increase to nearly R2000 in the next three
years.
Eskom offering rebates of between R4,200 and R12,500 per
system.
Investment Appraisal
The investment required for a solar geyser ranges from
R9k – R22k (after subsidy).
Typical monthly electricity bills in Parkview are R1500.
Water heating with an electric geyser accounts for 40%.
Converting to a solar geyser would save R600 per month, on
average.
Payback Period
The payback period of converting to a solar geyser system
would typically be between three and five years (some individual
systems may have a longer payback period of eight or nine
years).
100 Litre System Costs
Rebate from Eksom
Equipment (100 Litre tank)
R6,000 - R7,000
Installation
R2,000 - R3,000
(Based on size of tank
installed, efficiency of system)
Total R8,000 to R10,000
‘Typical’ Parkview
Household
250 Litre tank
equipment and installation
Total R14,000 to R27,000
Estimated Net Cost range
R4,000 (+/-)
R4,000 to R6,000
Rebate from Eksom
Estimated net cost range
(Based on size of tank
installed, efficiency of system)
R5,000 to R7,000 (+/-)
R9,000 - R20,000
Useful Product Lifespan & Warranty
The average electric geyser has a working life span of 7 yearssome lower end solar geysers range between 8-10 years (some
solar systems have a 25 year life span).
SABS approved systems normally have a 10-year warranty.
Net Effect on Home Insurance
Standard insurance cover is available, some offer a reduced
premium for certain systems.
Insurers in South Africa require that solar geyser systems
comply with SABS standards and those demanded of Eskom’s
accredited suppliers.
Net Effect on Property Values
House value with solar heating installed increases.
SA realtors reported average was +7% with a peak at 11%
on properties valued at under R2.5 million.
EQUIPMENT OPTIONS
Choosing a solar geyser seems complicated - it isn’t.
Advantage is that the research has been done for you.
Eskom publishes useful guides
http://www.eskomdsm.co.za/library
HOT WATER REQUIREMENTS & SIZE SYSTEM REQUIRED
Don’t rely on electrical element, plan properly, limiting use of
the back-up element means you maximize return on your solar
investment.
50 litres of hot water per person + an extra 50 litres to calculate
minimum capacity of your solar water system.
Two types of Panels - ‘Flat Plate’ or ‘Vacuum Tube’
Vacuum Tube
Flat Plate
Collector Type
Flat Plate Collector (FPC)
Performance
FPCs tend to have better performance EVTs can reach extremely high temperatures and
than EVTs on ideal solar days.
are especially good for systems requiring high
grade heat in commercial or industrial settings.
Their efficiency drops off during the
Tend to perform better in the winter months due
colder months.
to insulating properties of a vacuum.
Cost
FPCs are typically less expensive.
Size/Weight
FPCs are typically 1.5 x 2m, however, ETCs are typically 1.5 x 2m, depending on the
some manufacturers provide variety of number of tubes in the collector.
sizes. Lighter
Heavier
A typical collector will weigh
A typical collector will weigh
between 50 to 60kg.
between 50 to 100kg.
The FPC cover is typically made of
Although evacuated tubes are made of hailsafe
tempered glass which is resistant to tempered glass but they can break.
breakage.
If broken, each individual tube can be replaced
If damaged, likely that the entire
easily and at relatively little cost without having to
collector would need to be replaced. shut down the system as each tube is isolated from
the collector.
Maintenance
Evacuated Vacuum Tube (EVT)
Typically more expensive than FPCs.
However, some EVTs can be relatively cheap.
EVT
EPC
CLEAR DAY
MILDLY CLOUDY
BTU/M2/DAY
CLOUDY
TWO TYPES OF SYSTEM AVAILABLE
Direct systems - water is heated-up directly
Indirect systems - water is heated-up via a heat exchange
mechanism and a transfer medium
TWO TYPES OF STORAGE SYSTEM AVAILABLE
Pumped storage – water is forcibly moved by a pump (also
known as a split-system)
Thermosyphon – the tank is placed above the panel- water
moves by convection (also called close-coupled)
THREE TANK CONFIGURATIONS
Standard installation should be selected if the existing electric
geyser needs to be replaced.
Pre-feed installation feeds solar-heated water into an existing
geyser when extra hot water capacity is required.
Retrofit systems possible- saves on cost of new solar tank.
WHAT NEXT?
what next?
• Those interested complete quote questionnaire online and tell others
• Asking for suppliers to provide proposals including pricelists and
discounts bids.
• select preferred suppliers (quality, terms, ability to deliver and price)
• users select supplier and product and sign up directly with supplier.
Discounts will depend on number of people signed up.
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Already have a system installed and are willing to
share your experience with us?
Please forward your contact details to us at
green@parkview.org.za
Want to become involved in the project
which will request quotes from suppliers?
PLEASE COMPLETE THE SURVEY
go to
https://www.surveymonkey.com/s/greenparkview
or visit the PRA website www.parkview.org.za
Should you have any questions or concerns about
the initiative, kindly email us at
green@parkview.org.za