Welcome – Solar-Worx Solar Power and Renewable Technology Database
The solar-worx site provided the latest developments in the fast paced world of solar power and green technologies. With global concerns over climate change, increasing oil prices, diminishing oil reserves and natural gas reserves and Government incentives for investment into ‘green energy’ solar technology is enjoying a global boom. We consider these trends, look at the latest in solar panel developments and the implications for solar power as a viable alternative to fossil fuel based power production.
My name is Steve Jones, i am a Physics Graduate and live in Perth, Western Australia. In my blog, i will focus on domestic solar power systems and large scale solar farms, up to 200MW.
With countries like Germany leading the way with clearly defined renewable energy targets and countries like Australia implementing a carbon emissions reduction scheme, solar power, along with wind power technologies, bio-mass energy and ‘hot rock’ technologies are no longer seen as ‘alternative’ energy sources but are vying to become ‘mainstream’ as world Governments mandate minimum renewable energy quotas. In the U.S. the Obama administration, despite strong pressure from the oil industry, is pushing ahead with solar power and renewable energy at large scale levels.
Solar Panel Efficiency Heading Past 20%
Solar panels in the early 1970′s were struggling to attain efficiency greater than 12 percent. In 2012 solar panels are easily reaching 10-20 percent efficiency and 40 percent is likely over the next 10 years. This will mean solar power is a viable alternative to large scale power plants dependent on coal or gas. A Chinese company Xing Zhu Solar has developed a new solar panel glazing technique that effectively focuses sunlight on the PV (photovoltaic ) panels, much like a magnifying glass might. This has the result of almost doubling the solar electricity produced. Shin Zhang on a visit to the C.S.I.R.O. was asked about the viability of this technology from a financial point of view and how effective this new solar power technology is: “It is effective. I haven’t heard of anyone else using this approach, and we did come up with it independently (4 years ago), but I’ve tested it, and it works well. It simply reduces the reflected light loss onto the P.V. panels.To its most basic question: does the gain through the glazing balance, exceed, or fall short of the loss through the same glazing, at the same time, for the temperature measured in the room? It’s a physical “window simulator” without all the room variables. The only reason it can’t be used to “accurately” calculate the net energy flux (besides the fact that there are so many variables that nothing really can) is that with increased temperature difference between the sensor box and the room, it falls more and more under the influence of “thermal leakage” between the two by convection between the glazing layers, conduction across the glass, and of course a minimal flux through the insulation of the box. This will make it read a slightly lower temperature differential than it would if it had its own “window” or custom spacers, thermal breaks, etc. in the glass unit to isolate an area at the sensor box. But, even in its simplest form it is absolutely accurate for “gain” “loss” and ”break even.” It’s also very good for “moderate” “barely” ”lots” etc. kind of evaluations that are most important to the people who reside in the structure. It could also be used in calculations to get a fair idea of how much energy is being absorbed by your total storage mass. If you wanted to use its data for that or for net gain calculations, I doubt that they would ever be off by more than a very few %, even at the extremes of..high gain/high ambient temp/cool interior, and the other end…..night/cold ambient temp/warm interior. The room factors would taint your numbers more than a little ”leakage” of the sensor box would. Mounting the box right in the room this way is the most reliable way to negate any ”leakage” for a break even evaluation. At the break even point the room and the box are theoretically at the same temperature thus, basically zero “leakage and of course, zero net gain/loss through the window. The thing about Solar thermal numbers is that they really aren’t ever any more accurate, than the weather is consistent. However equilibrium can still be trusted.
The graph above (Source: http://www.ph.utexas.edu/) demonstrates that as solar panel efficiency increases that the price drops almost exponentially. This is also a result of greater solar uptake and Government ‘green’ initiatives – Germany in particular has driven solar farming and offered significant solar rebates since 1997.
Storage of Solar Electricity
This has long been the sticking point of solar power . Even with a grid feed in system there has always been a need for a low cost method of storing solar electricity. Battery technology and the associated inverters are fine but expensive and not very efficient . A developing new technology, again developed in Australia is called supavoltaics. It uses a planar silicon wafer to capture electrons immersed in a radioactive gas, such as tritium. The technology mimics the mechanics of converting sunlight into electricity in a solar P.V. panel. Supavoltaics is now almost able to match solar panel efficiency because as the gas decays its electrons permeate a vapor which produces electron storage – similar to, but far more efficient than a lithium ion battery, currently in wide usage. The very simple process of a nuclear decay into a usable energy storage system with yield of 99.8 percent efficiency will possibly lead to a solar storage system suitable for domestic and industrial scale solar energy storage – this would revolutionise solar power and make it viable as a carbon free large scale alternative and true ‘green energy source’.
Solar Tracking – The Evolution of Solar Efficiency
Whilst we have discussed the trend in increasing P.V. panel solar efficiency, the relatively new arena of ‘solar tracking’ is where the most significant gains in output of domestic solar power systems up to commercial solar farms will be made.
It’s well recognized that a tracker can increase overall output by as much as 50% on a given day, and between 30 and 40% annually (cloudy days bring the average down). The commercial trackers are priced now at very practical levels for small or large (>200MW) arrays. N.E.C. happen to have just began selling an intelligent three-axis tracker, called the NEXSolaTracker . The systems controller is a linear actuator many, up to 200 PV panel mounts could be made tracker compatible for less than US$0.20 per watt or so. So lets say you have 3oo0 200 watt solar panels already at US$80 each, their tracking solution will give you as much or more watt for the dollar invested than another set of equivalent solar panels. Solar Panel trackers can maximize efficiency by greater than 13 percent. As to the development of non-glare solutions, that still can’t avoid the cosine loss of area due to the incident angle, which directly translates to loss of energy potential. Increased reflection at higher incident angles is an additional factor that is rarely calculated and makes off-axis efficiency even worse than the simple cosine function.Solar trackers essentially maximise solar panels efficiency, and implementation and cost make them compelling options in 2012.
How things have changed since we wrote the http://solar-worx.com/australian-state-and-federal-solar-power-incentives-case-study/ post. The now greatly reduced 8 cent feed tariff has sent shock waves through the Brisbane solar installation market. It is estimated that the number of solar installations in the Brisbane metropolitan area have shrunk by 30 percent since the reduction in the solar f.i.t. This takes into account the people who signed up for the 44 cent f.i.t. and have yet to have their system installed. The deadline for the installation of solar power systems to qualify for the 44 cent f.i.t. is 30 June 2013. After this date we expect there to be a further drop off in solar uptake. What a sad state of affairs – the incentives offered in Queensland to date have been very successful in promoting ‘green energy’ in the state with the most sunshine. The introduction of the much touted carbon tax was supposed to go hand in hand with the roll out of renewable / ‘clean’ energy technologies – including solar power.
The Future For Solar Panels in Queensland – Post June 30 2013?
Brian Rhodes a veteran of the Brisbane solar panel market claims that the Brisbane solar power market could well drop another 15 percent after 30 June this year. however, he predicts that the continued concerned over increasing Qld. electricity pricing plus ongoing awareness of green technology will prompt the gradual resurgence within nine to twelve months.
How Did The Feed Solar Tariff Cut Effect Prospective Solar Power system buyers?
Brian claims that the low f.i.t. environment makes solar system size matching to the residents daytime power usage more important than ever. Consumers with solar systems need to try and ensure they feed minimal power back to the grid (as they receive 8 cents, but pay 23 cents)
Update 4 April 2013 – Network Cost Drivers To Electricity Pricing 2013 – 2020
It is looking more and more like network costs (recent examples from N.S.W. and Qld.) are going to be the key drivers in determining future electricity tariff increases from now well into the 2020′s. The latest forecasts show that increases of the upgrade and repair of the networks for all Australian states could represent an astounding 30+ percent of the expected power price increases. Modelling is in progress at the C.D.A. and due to be release Q3 2013 – we watch with interest. This will have a major impact on solar power uptake in all Australian states as well as all other forms of renewable energy.
We commented in 2011 that the uptake of solar is being seen as a potential issue to the maintenance and cost of upgrade of the S.A. electricity grid. If the solar tarrifs remain in place in S.A. there is anticipated to be 4500 new solar panel installations around Adelaide before 2014. The main contributor of this is the feed in tariff which is generous in comparison with most other Australian States.
A 5kw system installed in Adelaide can have a pay back period of 5 – 7 years (ref: http://solarenergyinformation.com.au/). This is based on current S.A. electricity pricing and this will decrease as power prices rise. Financial returns on solar are estimated from 4 -15 percent per annum depending on F.I.T’s system size and orientation etc – given average U.S. and Australian stock market yields average 7 percent (source http://www.dowjones.com/) this is quite attractive.
Adelaide Solar Incentives
The Governments solar bonus scheme is being wound back – however it did its job with prices of residential solar installation down 75% since May 2006 – quite remarkable.
In the next post we look at Adelaide’s Solar Farms and their impact on reaching the 20 percent renewable energy targets
An interesting video i found on youtube from the ‘ClimateWorks’ Group. With over 900MW of solar P.V. scheduled for manufacture in China in May 2012, the 10GW target is easily possible in 2012.
James Obrien from the School of Physics sent me these interesting articles on setting up a simple ‘home installed’ solar P.V. test system and the much touted solar ‘Eco’ Roof System. With the solar power market in Australia on the boil, and prices on the rise James is of the opinion that with the aid of a C.E.C. electrician, solar installation is possible for 30 percent less cost than via commercial operators.
1. Suntech ‘Home’ Solar Array Experiment
Today was the first day for my brand spanking new solar system.
4 Suntech 250 watt panels
1 Blue Sky 3024i MPPT charge controller
1 temperature sensor
1 Cobra 2500 watt inverter
3 batteries (2 105 amp and one XXX amp) that came with my RV (five years old)
2 #12 11 feet from two panels wired in series
2 #12 7 foot from one panel in series with 2 #12 4 foot
X number of feet of #10 wire (prewired at Kustom Koach Factory)
4 foot #8 wire pair from charge controller to the batteries.
1 15 foot #10 wire from AC side of inverter to plug in shore power box.
four panels wired parallel from two series banks
6:15 am Charging started at 0.2 amps
7:00 am charge rate climbed to 1.6 amps
8:00 am 3 amps
9:00 6 amps
10:00 8 amps
11:00 12 amps
12:00 16 amps
1:00 13 amps
2:00 13 amps
3:00 10 amps
4:00 8 amps
5:00 slid from 7 amps down to 3 amps
6:00 1.6 amps
7:00 0.6 amps
8:00 0 amps
I had deliberately allowed batteries to sag then allowed the converter to bring
them to 13.8 overnight.
by 11:30 a.m. the batteries were being float charged (14.9 max voltage)
I then deliberately loaded down the system by turning on all the 1156 lights and
put the fridge on DC (30 amps) (16 amps draw) to see how many amps I could draw
from the panels. Voltage did not get below 12.9.
I had preheated the hot water heater on shore power–and the inverter and panels
were able to carry the load–and run the fridge on 12 volt as I trundled down
I hope this helps someone make decisions on Solar!
I forgot one set of cables. The DC cables to the inverter are twinned #4, i.e.
two positives and two negatives (because that is all the inverter connections
would accept). There is a 350 amp catastrophic fuse right at the positive
I simply have a plug in the shore power box that I slide the shore power cord
into. That removes all risk of ever accidentally “back feeding” the inverter.
The cables on the roof (11,7 and 4 footers) are also twinned #12–I was not very
clear in my description of that.
THE NUMBERS (for those of us who want to know).
As near as I can guesstimate the voltage drop from the solar panels to the
charge controller may be around 1% at maximum system output. It is impossible to
calculate because I have to guess at the length of the prewired #10. (not big
enough imho–but too much trouble to replace).
Voltage drop from charge controller to batteries should also be less than 1% at
Voltage drop from batteries to inverter at maximum inverter output is about
1.5%, but as I said earlier–there was no way to use even larger cables.
Voltage drop from the AC side inverter to shore power cord box is less than 1%
at full output.
I’m pretty happy. The install took two days because I had no mounts for the
panels so the installer (my cousin, a registered electrician) had to fabricate
them from scratch. He is also a bit of a perfectionist, he milled conduit where
ever there was a tin lining penetrated to prevent chaffing of the insulators and
cord covers and used special oil and water resistant cabling–which I will
forever be thankful about.
He ran a 110 volt cable to my sewer valve box so that I can place a small heater
there during our super cold winters (why don’t the manufacturers wise up?) and
also ran a cable to the rear end of the RV for use with my generator.
Today I’ll be having the unit cleaned–and the lady that does the work *loves*
to vacuum. I’ve preheated the water on shore power (1120 watts for a ten gallon
water heater)–but will switch over to solar for the day just to see how the
system performs in “real life”.
Solar Roof – My Thoughts
After a lot of media attention, i thought i would chime in on the ‘solar roof’ concept, doing the rounds currently. I am confident that the option of condensation on the inner cover, by using a thin liquid film flowing over the topside to cool and maintain the cover at the dew point temperature, will be your best result. Simple, low-cost, effective and the solar UV exposure (at the glazing) is effective to prevent mould. A 2000 square foot project will produce the quantity of condensation your refer to – a rule of thumb is one pound condensation per sq.ft. of glazing area (needing also an equal area of leaf canopy for transpiration) per day.
This is the anticipated result of SolaRoof operations and the LiquidCoolingFilm can be implemented within the bubble cavity or the inner cover can be a double layer to contain the LiquidCooling flow separately from the BubbleCavity. The circulation can be set up for thermal exchange with cool LiquidThermalMass and/or coupled to external ColdWaterResources. SolaRoof also has an option of an inner cavity (using a 3 layer roof construction) so that the cooling liquid can be other water or water based liquid that, using air flow in the inner cavity, can chill the CoolingLiquid by affect of evaporative chilling of the thin liquid film. (search WikiWords at the SolaRoofWiki for more info – and help write our wiki knowledge base)
I like your information and approach for the calculation of CO2 requirements of plant photosynthesis. Studies have shown that the uptake increases (perhaps in a linear relationship) with the increase in CO2 in the leaf canopy. Maintaining the CO2 concentration at twice atmospheric could, for example double the grown rate for twice the uptake of CO2. Data on such relationships is very limited – studies at full sunlight have probably not been done. Theory is generally not well supported with any data at larger scale – but is extrapolated from laboratory scale studies and theory.
SolaRoof projects are capable of producing the environmental conditions that would enable extensive study of such important issues at large scale and is also capable of cost effective exploitation of these techniques to maximize yield in commercial scale Controlled/Closed Environment Agriculture.
Where would you establish the project that you propose for studies? I am looking for American teams to collaborate with our EU research and development program, recently selected for funding (in Europe) by the Eco Innovation program. I can connect you with the key scientists who are leading our team and now organizing to implement the F2W2F (Food to Waste to Food) for regenerative, local food from food waste. In this system we use anaerobic digestion followed by aerobic stage conditioning of the liquid fraction of the biodigester output, which is then used for food crop irrigation. Our CO2 is sourced from the combustion of the BioGas (for purpose of electrical power generation), with the goal of containment of the resulting CO2 within the SolaRoof greenhouse. The gaseous, liquid and solids produced by the BioDigestion of the organic waste are therefore not “released” or “disposed” but are utilized for local, community based food regeneration. The balancing of these inputs and outputs is the the goal of the current study. We are seeking good theory for guidance of project design and our results will be a source of data – generated from 3 Pilots (1000 FT2) and one Demo (10,000 FT2) projects that will operationally gather a substantial data base for analysis.
School Of Physics / Solar Photovoltaic Studies
The Australian Government has a 20 percent renewable energy target – see http://www.climatechange.gov.au/government/initiatives/renewable-target.aspx. The target is set st be reached by 2020 which many thought was ambitious. In fact – States like S.A. have reached 22 percent already , mainly due to the rebates available for solar power installation.
In Queensland the State Government has a solar rebate that pays home owners 44 cents per KWH for excess solar electricity fed back onto the Queensland energy grid – this represents a 220 percent premium to the standard electricity rates paid, currently 20 cents per KWH. In Brisbane, alone there have been 32,ooo solar power installations since January 2012. The solar power Brisbane website reports that the new Queensland Government could reduce this solar rebate. Whether the solar panel industry in Brisbane would survive such a cut remains to be seen. The solar industry in Brisbane employs over 12,000 people directly and possibly over 120,000 indirectly, supplying the solar panels, solar inverters ,railing systems for the mounting of the solar panels etc. The electricians installing solar panels in Brisbane must be Clean Energy Council (C.E.C) approved and it is estimated that over 11oo have under gone the training to gain the C.E.C. accreditation.
Size of Solar P.V. Installations in Homes In Brisbane:
A breakdown of solar panel installations in Brisbane in 2012, by KW rating is as follows:
Solar System Size (Brisbane Australia, 2012) Percentage of Installations
(Source: Solar Panels Brisbane )
As you can see, the smaller solar power systems predominate in Brisbane – mainly 1.5KW. However it is also interesting to note that 32 percent are greater or equal to 3 KW. The price of solar panel systems in Queensland has dropped as a direct result of Government solar bonus schemes and feed in tariff rates. The cost per watt of solar power installation has dropped at a rate of 15 percent per year over the last seven years.
Solar Power Brisbane Prices – As an example, in 2008 , a 1.5KW system could cost, in terms of ‘out of pocket’ around $5000 , in April 2012 there are Brisbane solar power companies offering systems for less than $1000 – an 80 percent drop in price! We do not think this trend is sustainable – when Governemnt incentives for solar power reduce, we expect to see prices increase again.
This downward trend in Australian P.V. pricing has happened in many countries – well before Australia. The following chart demonstrates Japanese Solar Power Installation prices up to 2002. The trend in solar pricing is virtually identical to what is happening in The Australian solar power market since 2009.
Solar Power in Melbourne Australia
The Australian solar power and solar panels installation have grown by over 20 percent per annum since 2009.
In July 2011 there were 1100 Melbourne home owners getting bids on getting solar panels installed on the roof of their house according to the A.B.S.They may not be technical people and do not intend to build or install the panels themselves. Websites have sprung up like the solar panels Melbourne information portal that allow anyone an impartial source of information on Melbourne solar installation and access to check specifications and ratings on the different “brands” of solar panels and Melbourne solar power installers. Each company in the solar power industry always say their solar panels are the most efficient. People are always advised to have two bids or possibly three before committing to a particular installer.
Many low income earners cannot can’t afford to pay upfront for solar power but the Federal Government solar scheme offers up to $3000 to assist in the initial Melbourne solar power installation. Most Melbourne residents would much rather pay a solar panel installation company than the electric company which of course will just keep increasing the power prices once the carbon tax is bought in, in 1 July 2012 . A finance loan for solar panels would be payed off in 3 to 5 years typically.
Many people wonder if there is a relatively inexpensive tool or solar meter for you to leave outside for a day in a particular location, that can measure potential solar power generated by your solar panels? The solar meter installed in your Melbourne meter box does just that . People with shading onto their solar panels report often that they are not happy about shading in the morning due to large trees on their property. If they are unable to cut the trees down they can consider to have another location on the roof for their solar panels provided it is a northerly direction – optimum for Melbourne solar panel installation. The Northern side of your roof is the best location with solar in mind. However, not knowing much about solar then, people have installed their solar panels in a NNW or NNE direction with a typical loss of around 15 percent solar output. Before moving the panels, or install more panels we suggest contacting a C.E.C. approved Melbourne solar installer and discuss the options. Remember solar panels are also an investment in your property and can up up to 3 percent value to your home. from this point of view, if, for example you have a $500,000 valued home, then a 3 percent increase in the value based on solar panel installation equated to $15,000. This is considerably more than a typical $3000 to $5000 cost of initial solar power installation on offer in Melbourne currently.