Reprint from Hansard
ELECTRICITY (RENEWABLE ENERGY PRICE) AMENDMENT BILL
Adjourned debate on second reading.
(Continued from 24 February 2011.)
Mr PEDERICK (Hammond) (11:07): I rise to support this bill which was introduced by the
deputy leader, Mitch Williams. I will go through some history of what has happened with feed-in
scheme legislation in this place. On 14 February 2008, the parliament passed the Electricity
(Feed-In Scheme—Solar Systems) Amendment Bill 2008, which enabled the state’s solar feed-in
tariff scheme to come into effect on 1 July of that year.
This scheme provides householders with a 44 per cent rebate on electricity that they feed
back into the grid from photovoltaic electricity systems installed on their roofs. This is a net rebate
and is only paid on electricity that is fed back into the grid; that is, at any time during which
electricity is being consumed at the site where the photovoltaic cell is installed, only electricity
generated in excess of that instantaneous consumption is fed back into the grid.
For example, if a refrigerator thermostat switches that refrigerator on, it is most likely that
while it is running, there will be a net draw from the grid but, most likely, when it goes into standby,
there may be a net input of energy into the grid. This is metered independently of consumption
from the grid and is used to calculate the rebate. The rebate is funded directly on an additional
electricity charge approved by ESCOSA and impacts on the electricity bill of every electricity
consumer.
Prior to this bill being passed, retailers were buying solar electricity from householders at a
one-for-one rate, but after this bill was passed many retailers stopped paying for solar electricity
themselves and, instead, allowed ETSA to pay the 44¢ per kilowatt to householders for their solar
electricity, with the 44¢ collected as an additional charge on all electricity consumers.
Retailers are now profiting from the scheme by onselling electricity so generated back to
consumers. AGL and Origin were paying something in the region of 16¢ to 24¢ per kilowatt hour for
electricity fed into the grid prior to the feed-in bill being passed; if they continued to pay this,
retailers would now be receiving up to 68¢ per kilowatt hour for their solar electricity with the
44¢ legislated premium.
As part of the original legislation, it was deemed that a review of the scheme would be
triggered at 10 megawatts of solar energy capacity being installed. This level was reached in
May 2009, and on 31 October 2009 the government announced the terms of reference for a review
of the scheme. The report of the review was eventually released in August 2010—well after the
March election of that year—making nine recommendations.
It is interesting to note that industry is currently trying to work under the recommendations,
but they have not been formally approved by the government. These range from recommendations
involving the government considering an approach similar to the ACT model, and include a
provision in the legislation for the minister to recommend other technologies into the scheme, and
recommendations about implementing a cap similar to the Victorian scheme. It was suggested that
the cap be about 100 megawatts capacity, and there are some suggestions that the
South Australian cap would possibly be 60 megawatts, and I believe we are very close to that
number
ELECTRICITY (RENEWABLE ENERGY PRICE) AMENDMENT BILL
Creatherm Hydronic Flooring System
Another attractive alternative to the ThermalBoard system is the Creatherm system. This polystyrene material has a compressive strength of 36 psi, and the typical load of a concrete footing placed on top is approx 1 psi. The pipe is simply stepped into place at a spacing or 2 or more (usually 4) channels apart. This gives a degree of flexibility with regard to spacing the pipes and the material is very suitable for outdoor or other moisture prone uses. The R-value of the polystyrene is excellent as we know, and the panels are available in three thicknesses, with R-values of 5, 9, and 11. Where high strength is required or moisture is a problem, this system will last better than Thermalboard certainly although thermal responsiveness will never be as good and this affects efficiency. The huge thermal mass of concrete over the top naturally makes it not very reactive and maintenance would be a problem of course. The raw material is made by BASF and it is made under licence in the USA and other places. No Australian distributor is indicated.
Readers will know of my interest in ice skating and rink construction. It occurs to me that this is the perfect substrate for putting beneath a new generation ice rink, utilising 3/4 inch PEX instead of copper pipes.
Collector Installation
Here in Australia, a system must be installed by an accredited plumber to qualify for RECS. Now there are some plumbers who have never done much roof work, and who would like to do evacuated tube installations. These plumbers are encouraged to get some advice from their suppliers before attempting a job. In the meantime they might be interested in this quick reference based on experience and thermodynamic simulations.
Evacuated Tube Collectors.
The evacuated tubes are made from glass and though they can handle quite a bit of impact they can break. When unpacking, ensure that the bottom of the tube is a shiny silver colour. If it is white it indicates the tube has been broken and it has lost its vacuum.
We recommend that the tubes are left in the box until they need to be inserted into the manifold. If left uncovered in the sun the copper heat transfer tip can reach temperatures of up to 250 degrees, which may cause burn wounds.
The optimal position is facing North. However the ET collectors are more forgiving than flat panel collectors. If a North pitch is not possible, then for a typical 22 degree low pitch roof the performance coefficients are (for Adelaide): North: 1.00, East: 0.94, South: 0.74, West: 0.76. As you can see, even a south-facing array will still perform reasonably well. For steeper pitch roofs, the penalties are more severe: For a 40 degree pitch, they are: North: 1.00, East: 0.94, South: 0.55, West: 0.66.
For ET systems, the minimum mounting angle is 15 degrees. Since roof angles are normally between 22 degrees and 45 degrees the collector can be mounted flush on the roof. If however the collector needs to be mounted on a flat roof, a stand giving the collector a minimum tilt of 15 degrees is required.
Partial shade is not as degrading of performance as for a PV panel. The degradation is directly proportional to the area covered, and can often be tolerated. With all split-system solar installations, you should try to minimise the pipe run between collector and tank, and try to keep it below 10m. The pipe diameter is dependent on the area of the panels. For heat pipe ET collectors, a common recommendation is 15 litres per hour per square metre of collector. Say a typical collector is 4 sq.m. The nominal flow rate that should be designed for is therefore 60 litres per hour or 1 litre per minute. You should also ensure a flow velocity of no more than 1m/s to ensure smooth low friction flow, therefore for the example above you first calculate the cross section of the pipe.
A = cross section of pipe
V = volume of water per minute (1 litre per minute)
L = max flow velocity (60 metres per minute)
A = V / L
Giving A = 1/6 sq.cm
Now r = sqrt(A/pi) = 0.23cm. Therefore you will need an inner pipe diameter of at least 0.5cm. Anything larger will be fine and the formulae above will help with larger arrays.
High quality lagging must be fitted well along the entire length of the collector loop with the possible exception of where the pipe passes through the flashing. Experience has shown that the flashing MUST contact the hard surface of the pipe in order to make a good seal. Ensure you push a little excess lagging onto the pipe so that there are no anywhere gaps later. Gaps in your flashing are very bad for system performance, no matter the weather and no matter the climate.
Roof Mounting and flashing
On cement tile roofs use galv metal strips to fasten the solar hot water collector. Simply remove the tiles, fasten the strips to the roof trusses and replace the tiles. On colorbond or other metal roofs you use a special padded foot which bolts onto the collector frame, and is screwed to the corrugations. The aim with metal roofs is to prevent galvanic corrosion by ensuring that the steel frame is not in electrical contact with the roofing metal.
Taking the insulated copper pipes through the roof
Plan the location of the two roof holes taking into account the thermal expansion requirements of the copper pipe. Pre-bend the copper pipe as required. Check the location of the hole. Drill the holes, then fit the flashing around the hole. Off-the-shelf flashing such as Dektite is recommended. The manufacturer will have installation recommendations. Pass the pipe through the flashing. Next slide the lagging onto the pipe, and push another 10% of lagging (e.g. 1.1m of lagging on 1m of pipe) onto the pipe length. Now fit the pipe to the collector manifold either using the screw or compression fitting as recommended by the installation manual.
Run the piping the rest of the way to the tank. Connect the return from the collector to the correct inlet of the tank. This will be marked in the installation manual. If you get this wrong, then you will have poor tank stratification and your solar system will not work well. it is recommended that you fit a backflow prevention valve before the hot water inlet of the tank in order to thermal losses due to backflow into your tank when the pump is switched off.
Finally paint all the lagging to prevent it from turning to powder withing a few years. Some people have mucked around with expensive aluminium foil but experience has shown that a coat or two of normal house paint is best.
We suggest that you ask your plumber or installer some questions along these lines, to see whether they have the experience and understanding of the task they are undertaking. At the very least, they will know that you care more about the finer details than some of the other customers. It can only help to increase the quality of the job, which might make a big difference to the overall benefit you are achieving.
Irritation grows over delayed Report
Public irritation over the Rann government’s delay in releasing the report into the solar panel industry in SA. Today marks the one year anniversary of the announcement of the report. The Greens MLC Mark Parnell today said that the government had been sitting on the completed report since Christmas. The major expectations within the review are presumably whether or not it recommends widening the scope of the existing program to installations exceeding 10kW installed capacity, and whether it will recommend compelling electricity retailers to pay producers the full retail cost cost of every kWh produced, in addition to the 44 cent incentive payment. These are two of the measures currently being demanded by the Greens’ current PV policy.
While it is always pleasing to see the Greens pursue a widening of the PV scheme, this correspondent has yet to see any comments from the South Australian PV industry indicating similar impatience. I strongly suspect that right now, the market is suffering a skills constraint on growth and that increasing consumer demand is not going to lead to a more orderly industry.
More on Hydronic Heating
Soon after writing the previous post on hydronic heating I came across a system which seems to me superior in a way which is simple for the layman to understand. This system is the thermalboard system ostensibly from the US. This is basically aluminium-covered MDF board which has the tracks for the piping routed into it. You simply screw it down and then tramp the piping into the tracks. The Aluminium overhangs the tracks so when the piping is inserted, it naturally contacts the aluminium. This system has the advantage of a smaller thermal mass and the heat-spreading characteristics of the aluminium means that the system is very responsive. The website has several PDF documents which spell out the exact benefits.
There is a news link which announces that this system, which was previously only recommended over timber is now available in an onto-concrete version. This requires simply a moisture barrier such as a membrane, or a polyurethane moisture mastik.

Hydronic Heating

Hydronic heating is becoming a realistic option in Australia now that efficient heat pump and rooftop solar collectors are available which work efficiently in winter. Hydronic heating refers to using hot water to heat a space using either in-floor coils, or wall-mounted radiators.
Wall-mounted radiators are ideal for renovations or where the homeowner does not want to replace the floor. The radiators typically operate at 60C so a heat pump system is not appropriate and the homeowner must use a solar collector.
Where a new dwelling is being built, in-floor coils are an option. As these run at a lower temperature of 40C, a heat pump can be used to drive them. Usually the coils are placed in the main living areas of the house, such as living rooms, dining areas, kitchens and bathrooms. Bedrooms are often not heated, although childrens’ bedrooms may be an exception.
Wall-mounted hydronic systems have always been popular in Europe. Usually these were driven by a central steam boiler and operated at 70C+. Because of the increasing use of solar collectors, these are now almost obsolete in new buildings, and builders now prefer pumped water circulation systems operating at a lower temperature.
In-floor heating is even more comfortable as very little convection occurs, and the perceived warmth is mostly radiant from the floor. The advantage is that the system operates at lower temperatures, is therefore more efficient. With evacuated tube collectors and sufficient solar storage capacity, the system can provide a greater fraction of the heating requirements.
These coils are from a durable polymer called PEX which typically comes with a 25-year warranty and a quoted lifespan of 250 years.
either a) laid into the concrete when the slab is poured, or b) laid on insulation sheets then screeded in, or c) laid on insulation sheets, then covered and the screed is laid on top, or d) laid on insulation sheets, and then covered by hard flooring. Many different systems compete in the market place. Arguably, if the concrete is to be covered with hard flooring, then the coils need not be laid into the concrete. The advantages of in-concrete coils are that the concrete slab has a very large thermal mass and this will retain a lot of the heat which is required. The other advantage is the superior load-bearing characteristics. The disadvantage is that this system has a very long time lag, and that the coils cannot be replaced.
In Europe, which is much colder and where heating is a higher priority, there is a wide choice of options. Surveying the industry we find the following hydronic heating manufacturers and specialist installers in Germany:
Aquatherm, Emcal, Fraenkische, Gabo, Giocomini, Havekost, Hewing, IBB, Janssen, JOCO, Jupiter, KAN-Therm, Kermi, KME, Lindner, MAINCOR, MAIR, Norit, Oventrop, Purmo, RIT, Rehau, Remo, ROTEX, Roth, Schuetz, Sigmund, Solar Leidig, THERMOLUTZ, Uponor, Variotherm, Viega, Vogel-Noot, Wavin, Wieland, Zewotherm.
Choice Magazine article on Solar Hot Water
Choice Magazine have a free online article with a little bit of useful information on solar hot water heaters. While it will give a good backgrounder on the subject, it is not a comparison of available components. One feels that the authors of the article were not quite clear about how this might be achieved. It’s true that it would be quite difficult in such a large country with its different climates, energy options and water qualities.
Perhaps what they should have done was to confine the scope of the inquiry not to systems but to components. That way perhaps at least the industry practitioners who are constantly putting together new systems, would have a little more qualitative information with which to make the choice. I feel that with a system where the components are customised almost with every installation, the idea is not to educate the consumer, but the industry.
The methodology of evaluating solar hot water systems should be to compare like with like. Comparing a flat panel collector with a heat pump system is just not good enough and ends up confusing readers.
Exactly how much is 6 square kilometers?
Nanosolar have stated that approximately 6 square kilometers of land will be required to produce 1GW of nameplate solar capacity. How much land is this really? Well it is a square of 2.44km on a side. I have superimposed such a square over the site of the Leigh Creek coal mine in the Gammon Ranges in the Australian outback.

Where is this in the scheme of things? Let’s zoom out.
So in Summary the footprint of a solar farm is less than the footprint of a typical coal mine supplying a similar amount of coal-fired generation. In addition, the land between the collectors can still be utilised for grazing. The coal mining operations also require precious water, which is not required for PV.
The PV solar farm may make a lot of sense for some communities. The concentrating PV operations like Solar Systems, might take note.
The new stars of Silicon Valley
The new stars of Silicon Valley are the scientists engineers and business people of Nanosolar in Palo Alto. Having taken their website down last week announcing that they would be back on September 9, they were true to their word. Speculation was that perhaps a takeover was in the wind. Thankfully this did not eventuate. Instead the announcements were positive milestone achievements which might silence the critics of the last few years. On Wednesday Nanosolar announced to the world the completion of their factory producing their new Nanosolar Utility Panel (TM) in a factory in Luckenwalde, and immediate availability of the panels. This factory is a state-of-the-art robotic assembly plant incorporating the foil cells being made in Palo Alto. The capacity of the panel plant is currently 640MW per annum. Manufacture of the foil utilising their funky CIGS ink, is possible at a rate of 1GW per annum per machine. The machine looks like a $2m capital item and it would not be a stretch to fit 20 of them in a small factory. The days of the 20GW p.a. manufacturing site are now here. Panel assembly will have to keep up. If I was making silicon wafers for photovoltaics, I would be looking worried today.
The contractual commitments from power companies and other partners, is about $4.1bn. It appears the $0.5bn invested by the venture and private equity partners, including the likes of Sergey Brin and Larry Page, have been well spent. The list of investors has been pulled from their website, but the google cached version shows these investors:
- Mitsui – the 300 year-old Japanese keiretsu.
- Carlyle Group – largest investment group in the world
- Swiss Re – the largest reinsurer in the world
- Benchmark Capital – the eBay financiers
- Lone Pine Capital
- Mohr Davidow Ventures
- EDF – the world’s largest energy utility
- Energy Capital Partners
- Klaus Tschira’s First Ventury
- Jeff Skoll
- Pierre Omidyar
- SAC Capital
- GLG Partners
- LGT Capital Group
- Grazia Equity
What gives with Nanosolar?!
The Nanosolar website is blacked out with a simple message saying please check back September 9. They are obviously gearing up for a major announcements. Speculation on other websites centers around a big announcement confirming massive commercial production ability and the general ebay availability of these printable nano-dye solar cells which have previously only been available to their German partners, and have been promising the under $1 per watt price point holy grail.
Myself I disagree – I sense a takeover by a global behemoth. Dupont? 3M? Dow Chemical? General Electric? Westinghouse? Exxon? I shudder to think. Perhaps it’s positive but I tell you what – I hope it’s not a silicon wafer manufacturer. I would hope and expect the government to step in. Why? Because there is a chance of skullduggery if this is the case.
Certainly there is cause for concern. Silicon cell manufacturers are now a powerful market force. They stand to lose their livelihood overnight if the economics of nanosolar are realised. There are potentially thousands of jobs which are threatened. The intellectual property has a huge strategic importance and it really should not be controlled by forces which are sympathetic to the status quo. That is to say, forces which have a large sunk investment in the existing silicon-based technology.

