Opinion on solar system. - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: May 03, 2013, 10:09:31 pm
content: I'm quite close to ordering a home solar system.Definitely want a Sunny Boy SMA TL inverter even though more expensive.But I know nothing about the solar panels.One company has offered a 3KW system with SMA Sunny Boy 3000-21TL inverter and 12 x 250w Trina ‘Honey series’ poly panels for $4690 + meter install ($330-$400)http://www.solarchoice.net.au/blog/wp-content/uploads/Trina-Honey-Solar-Panels-Spec-Sheet.pdfA 2KW system is $3490 + meter.Or a "premium" system of 12 x 250w LG mono X panels for $5190 + meter.http://www.lg.com/us/commercial/monox-solar-panelsThey are pushing the LG panels with this:QuoteAnother company with same inverter wants $5000 + meter for 12 x Suntech 250watt panels.And another company with same inverter wants $4490 for 12 x ReneSola 250W Virtus2 JC250M-24/BBV-2A real bottom dwelling cheap arse 3KW system with 12 x 250W Schutten Mono Crystalline Panels and Delta inverter is a low as $3299 (not $4299 as advertised)http://www.eurosolar.com.au/solar-power-systems/systems-with-250w-solar-panels/3-0-kw-solar-system/Using JFY inverter that goes to $3499Panels will go on the WNW roof at 311 degrees.Video of the late afternoon sun from 4:00pm to 6:28pmOpinions?

author: 4to20Milliamps
author_rank: Regular Contributor
timestamp: May 03, 2013, 11:23:16 pm
content: I've installed quite a few solar systems over the last ten years, the newer generation of solar panels are pretty robust, one thing to watch out for are the way the connections are made to the back, stress on the junction boxes causes a majority of failures.A high quality panel that has good encapsulation and extra support will be more crack resistant:http://www.kyocerasolar.com.au/assets/pdfs/we_are_in_the_details.pdfhttp://www.kyocerasolar.com.au/australia/index.php

author: mikes
author_rank: Regular Contributor
timestamp: May 03, 2013, 11:37:55 pm
content: My opinion on the solar system is that Pluto reallyisn'ta planet.

author: SeanB
author_rank: Super Contributor
timestamp: May 04, 2013, 05:47:13 am
content: Good idea, just choose one or the other. Monocrystalline panels are more efficient normally though in direct sun. Just choose panels that have the best efficiency, and the longest warranty.

author: Lightages
author_rank: Unknown
timestamp: May 04, 2013, 06:11:01 am
content: I would like to add that Kyocera panels, although not the cheapest, are really robust. I would not hesitate to buy more. For a time I needed my solar energy working and did not have the frame for the panels built yet. I place the panels on the ground and one day a strong wind picked one up and it flipped/flew and landed corner first into the panel next to it. Nothing but a bit of a scratch in the panel.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 04, 2013, 02:17:37 pm
content: You might be able to save a lot by connecting the solar panels to the rackmount UPS through a MPPT controller and using the UPS as the inverter. Not all UPSes can do this when plugged in (many older rackmount units could), so to test, plug the UPS into a power meter, plug a load into the UPS, and try adding power right at the battery with a bench power supply to simulate the solar panels. If the input power drops significantly and the battery voltage stays at the float point (even when fully charged), you've got a great UPS to use as an inverter. The MPPT controller is pretty easy to build (it's just a DC/DC converter with a microcontroller) and would make a great open hardware project. (In the meantime, you could just get a close match between the panel MPPT voltage and the battery float voltage and just use a simple overvoltage disconnect and blocking diode.)Assuming you do need to buy an inverter, Delta is a very good brand.

author: 4to20Milliamps
author_rank: Regular Contributor
timestamp: May 04, 2013, 02:48:38 pm
content: Australia has a lot of good solar resources, this place a has bunch of different manufacturers and technologies set up for anyone to go have a look at:http://www.dkasolarcentre.com.au/http://www.dkasolarcentre.com.au/flash/processmap.html

author: mtdoc
author_rank: Super Contributor
timestamp: May 04, 2013, 06:55:32 pm
content: Dave-Solar panel efficiency is unimportant unless you have limited roof space or you are mounting on a tracker or a pole mount in which space is at a premium. The efficiency of all modern, commercial solar panels are within a few percentage points - since you look to have a pretty large roof area to work with efficiency should not be a deciding factor.Similarly - all the large solar panel manufacturer's warranties are pretty similar these days - 10 yrs workmanship, 25 yrs performance with a derating for age. It's true that many solar panel companies have gone belly up so the stability of the company for warranty purposes might be something to consider - but the truth is that solar panels rarely fail. In the rare case that their performance falls out of spec - this will likely show itself right away.Mono versus Poly crystalline - also a non issue. Mono panels are generally slightly more efficient (non issue - see above) but any other differences (sunny vs cloudy performance) is minimal.Bottom line is that solar panels have become a commodity product and all the large (mostly Chinese) manufacturers produce similar quality panels - despite the marketing hype. There surely are some cut rate - poor quality panels being made somewhere but it's unlikely any professional installer is going to use them. Trina solar and LG are going to be similar quality.With similar quality and warranties - the solar panel companies are all competing on price (and marketing hype) - with large quantities now available to consumers here it US at less than $1.00/watt.Inverter quality and features do vary. You can't go wrong with SMA. High quality (German engineering and all) - but you'll pay for it.What IS very important for someone like yourself getting a professionally installed grid-tied system is the quality of the installation - ESPECIALLY the mounting to the roof. Poor workmanship there will cause problems- roof leakes, damage during wind storms, etc.Also - one factor that has been prove to have fairly large effect on performance in warm climates is the distance off of the roof that the panels are mounted. Temperature has large effects on panel perfomance and without adequate ventilation under the panels performance will suffer.So when deciding between installations - I would focus on the reputation of the installers, how they physically mount to your roof and how high of standoffs they use to get the panels up to ensure adequate ventilation.A couple of great rescources:PV Watts2 Calculatorlets you model the solar array output at your location using various parameters.TheNAWS forumis the premier forum for solar electric and other renewable energy.Good luck.

author: peterthenovice
author_rank: Regular Contributor
timestamp: May 05, 2013, 03:23:10 am
content: dave check this out

author: Psi
author_rank: Super Contributor
timestamp: May 05, 2013, 04:14:51 am
content: Quote from: mikes on May 03, 2013, 11:37:55 pmHeheWhen i saw the topic title i thought... "hm.. well, i'm not against the solar system"

author: Joules
author_rank: Contributor
timestamp: May 05, 2013, 09:35:52 am
content: Should have hired a skip when it was built than leaving all the left over rubble and trying to give it a fancy name "Asteroid Belt"

author: EEVblog
author_rank: Unknown
timestamp: May 05, 2013, 09:56:18 am
content: Quote from: mtdoc on May 04, 2013, 06:55:32 pmYep, that's what I figured as well.QuoteYep, I'm paying a lot extra for the best quality here, but I think will be worth it. Plus I like the SMA's Bluetooth interface.QuoteYeah, looking to go with this mob:http://www.ahegroup.com.au/Local, no negative reviews that I can find, and they are saying the right stuff I expect to hear. Some of the others weren't saying the right stuff, or any stuff.Even have their own Whirlpool thread:http://forums.whirlpool.net.au/forum-replies.cfm?t=1484224&p=13

author: Joules
author_rank: Contributor
timestamp: May 05, 2013, 10:00:23 am
content: On a more serious note... My vote also would be for Kyocera. It was one of the most efficient at the time we purchased and backed by a large company that should still be in business for the entire life of the warranty. Several years trouble free service so far.

author: EEVblog
author_rank: Unknown
timestamp: May 05, 2013, 10:23:11 am
content: Quote from: Joules on May 05, 2013, 10:00:23 amNone of my locals installers seem to offer those.

author: ee851
author_rank: Regular Contributor
timestamp: May 06, 2013, 01:01:02 am
content: OMG, Dave, I thought you were talking aboutthe Sun as the provider of energy for all forms of life in this solar system.My bad.For photovoltaic systems, be aware the cooler the cells, the more amperes they will output.www.homepower.comis a good resource for the nuts & bolts of making a PV system work for your home

author: jnissen
author_rank: Regular Contributor
timestamp: May 06, 2013, 10:40:07 pm
content: If you have any shading at all it's well worth the cost to go with micro-inverters. Enphase here in the US makes a great product and they are distributed all over. The SunnyBoy your thinking of getting is OK but one bird turd on the panel will result in the whole string suffering. Microinverters are per panel and allows you to monitor per panel production. I have an array that I installed the last couple of years and it's working great. So glad I went with the micro-inverters over the single or multiple large inverters. Dirt and leaves along with partial shading is real and will significantly impact your production.Example of a large array:https://enlighten.enphaseenergy.com/public/systems/f9CW28621

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 07, 2013, 12:48:21 am
content: The main disadvantage of such a design is that tapping into it for emergency power likely involves getting on the roof, something that is often impeded by the emergency itself. Maybe that's unlikely to be a problem in your area but if it does happen... Being able to pull just a few watts (or a few tens/hundreds of watts) can be very useful in an emergency. In theory, it's possible to make a gadget that simulates the grid and lets the inverters start,but it would need to potentially sink the entire output of the panels, not very easy with a large system. (If you don't pull enough power, the voltage will rise and the inverters will trip on overvoltage. In general, you either have to take it all or not get any at all.)A distributed DC MPPT design gives the same advantage without that disadvantage.

author: lemmegraphdat
author_rank: Frequent Contributor
timestamp: May 07, 2013, 01:35:42 am
content: Too me solar cells seem like a cool gadget but are they worth tearing into a good roof for? Could you place them on another part of the property?

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 07, 2013, 01:55:30 am
content: Thermal cycling is what often causes a roof to fail, so installing solar panels or painting the roof white are actually ways to make it last longer.

author: EEVblog
author_rank: Unknown
timestamp: May 07, 2013, 01:59:21 am
content: Quote from: lemmegraphdat on May 07, 2013, 01:35:42 amNope, not an option.I assume they use mounting rails, so there shouldn't be too many penetrators through the roof tiles.

author: EEVblog
author_rank: Unknown
timestamp: May 07, 2013, 02:01:21 am
content: Quote from: jnissen on May 06, 2013, 10:40:07 pmI thought a shaded panel simply was bypassed with diodes and wasn't too much of a problem?

author: Rerouter
author_rank: Super Contributor
timestamp: May 07, 2013, 02:15:18 am
content: i think he might mean for parallel strings as unless they have reverse polarity blocking diodes it would pull down the voltage of the others,

author: EEVblog
author_rank: Unknown
timestamp: May 07, 2013, 02:21:25 am
content: Quote from: Rerouter on May 07, 2013, 02:15:18 amYes. I'm reasonably sure my system will be series. The panels are circa 30V each, and the Sunnyboy inverter takes up to 750 input. So 12 panels can easily be done in series.

author: jnissen
author_rank: Regular Contributor
timestamp: May 07, 2013, 04:36:14 am
content: There are lots of good documented comparisons of series inverters and micro-inverters. I went with micro inverters as they were clearly the most long term bang for the buck. You can do what you want to Dave but in the long run you will likely kick yourself for not doing micros. The older string inverters are cheap but like I said one bird turd and the whole series string suffers due to the bypass diode series losses.Here is a good write up with recent comparisons.http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=9&ved=0CIABEBYwCA&url=http%3A%2F%2Flibres.uncg.edu%2Fir%2Fasu%2Ff%2FLee%2C%2520David_2011_Thesis.pdf&ei=GIGIUZn-MJLD0AGs9IHoAQ&usg=AFQjCNEpOkwga7YcKglVPZJSAOW_T7ov5w&sig2=YVq-X1elG4Oi1VprYNybdg&bvm=bv.45960087,d.dmQ

author: EEVblog
author_rank: Unknown
timestamp: May 07, 2013, 04:54:42 am
content: Quote from: jnissen on May 07, 2013, 04:36:14 amCan you put a real quantitative figure behind that?I find it hard to believe (without having researched it) that one bird crap will drastically reduce the output of a large series system. If so, almost every installed system on the market would be useless.

author: EEVblog
author_rank: Unknown
timestamp: May 07, 2013, 05:00:27 am
content: Quote from: jnissen on May 07, 2013, 04:36:14 amQuote:QuoteThat's for a 5% shading, presumably across all cells(?).So it kinda puts your your bird poo hypothesis down in to the noise.I'm not fighting for every last W on my system. So I don't see any major advantage in microinverter system (which no one seems to offer anyway)

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 07, 2013, 05:20:20 am
content: Something else to keep in mind is that if you keep the solar system voltage within 140-380V or so, you can run common switching power supplies directly from the panels in an emergency. Outside that range, you'll need a DC/DC converter to do that.

author: RickieSalad
author_rank: Regular Contributor
timestamp: May 07, 2013, 06:00:32 am
content: Hey dave.Sorry I don't have any solar experience myself but it seems to me that you could get the panels installed, and find yourself a highly qualified EE to design and build a nice inverter and related equipment.Unless of course it's one of those scenarios where "she who shall be obeyed"(I laugh every time you say that!) just wants to get it done. Then you don't have much choice but to just crack the wallet open and get that one checked off your "honey do" list.Either way it seems like I see an opportunity for a lengthy EEVBlog Solar/Greenie/Whatever you wanna call it, series of posts in the future.Even if you have to pay up for the commercial version to get it done, you could document and monitor the hell out of that system. Maybe use some of those garbage room PC's as data acquisition boxes. Maybe with a wealth of data to work from you could show all of your faithful viewers how a professional engineer would go about designing a system that would be better(tackling real world problems...YAY). Maybe multiple approaches, series inverters, micro inverters, etc to see what system truly works best outside of the marketing fluff.You could build and sell kits to folks with plenty of iron time to assemble their own, and fully assembled units for the uninitiated.All things "green" are pretty big so it seems like there could be a market, even if it ends up being relatively small, could be enough to help send Sagan to school and maybe buy the Mrs some shiny trinkets.In any event it seems like it could be quite the robust EEVBlog feature, article, post, series of posts, whatever you want to call it.

author: jnissen
author_rank: Regular Contributor
timestamp: May 07, 2013, 06:17:41 am
content: 5% is fairly easy to do with dust and bird dropping. Your not obliged to believe me or others as that is your choice. Just be aware once this is installed and you have sunk several thousand into it you will not likely want to spend more money to optimize it. You live with the limitations. Just look at your roof closely and if there are any vent pipes or antenna's in the area they will impact the power available. I have done lots of comparisons and the only systems that surpass the micros is tracking arrays. You also get per panel performance data from a micro array. I can find out if there is a particular panel that is under-performing and possibly clean it to improve performance.Did you already do all of the lighting and insulation updates? We are required to pass an energy audit prior to any type of utility rebate offer. Air leakage tests along with solar screens and other tricks yielded about a 15% reduction in my energy load prior to even doing any of the solar. 3KW may sound like a lot now but after losses you will be lucky to produce about 2600W on good days. I have 240W panels and the micro's are good for about 225W max output and rarely do I hit days where I max out the inverter. Heat, clouds, and passive losses all contribute and add up. To me solar is very inefficient. I mainly did it as my local utility was giving great incentives and with a tax deduction it made it a reasonable investment. Not many investments lately that can guarantee about 10-14% return on your money. I upgraded the system again last December. Now my bill is minus at the moment. It will likely go back into the red later in the year when our summer cranks up and the air conditioner runs more often. In general I have my system sized to cover about 80% of my usage. The utility recently changed the payment plan in our area. Now the solar installs that dump into the grid get paid what is termed a "cost of solar" net billing option. I get paid for every kWh I generate at a rate higher than what I pay to pull from the grid. Makes it economically feasible to have a larger system this way as your payback is sooner.

author: EEVblog
author_rank: Unknown
timestamp: May 07, 2013, 08:11:59 am
content: Quote from: RickieSalad on May 07, 2013, 06:00:32 amI don't think so!Apart from being illegal, they are not easy (read, difficult PITA) to design properly.It would costfar moreto design and build your own crusty one than it would be to buy the best unit on the market.QuoteSorry, not going to happen. Modifying an already installed system is not something I would consider doing.Maybe a few videos on measurements and data analysis, but that's it.

author: EEVblog
author_rank: Unknown
timestamp: May 07, 2013, 08:22:14 am
content: Quote from: jnissen on May 07, 2013, 06:17:41 amYou have provided zero data yourself, and just a link to some obscure research paper.Almost every system on the commercial home market is a single inverter installation. Are you really saying they are all crap and not worth spending money on?What are the quality brand micro-inverters?What is their longevity being housed up on the hot roof under the hot panel (this is Australia, you can fry an egg on the roof in summer)How much extra does the monitoring system cost with 12 inverters?There is likely very good reasons why almost all home solar installations are single inverter based.(BTW, it's all moot because I've ordered the single inverter system)QuoteYes, I can live with the small limitations over the more expensive multi inverter system.This isn't cloudy England, or worse, Melbourne, we get a lot of sun hereQuoteOur house is already very energy efficient.QuoteYes, obviously there will be a great variation in output power due to all sorts of factors. Angle, time of year, cloud cover, daily solar radiation level etc.QuoteWe used to have that in NSW. 60cents/kWh feed-in tariff, but now it is only 6 cents. Grid power is about 25 cents.

author: RickieSalad
author_rank: Regular Contributor
timestamp: May 07, 2013, 09:24:08 am
content: Quote from: EEVblog on May 07, 2013, 08:11:59 amahhhhhh! I had no idea if was illegal, some sort of regulatory thing I suppose.Well it would still be interesting to see some videos detailing the efficiency and such of the system.

author: Joules
author_rank: Contributor
timestamp: May 07, 2013, 09:57:42 am
content: Bird shit and dust is a myth... It's sunny here I haven't cleaned the panels in weeks and they have bird shit on them. My batteries didn't need much charge so only taking 75w in float. Switched on the inverter and started the lathe and the panels are now supplying 700w. This is with a 750w array that will easily supply over 800w (Kyocera conservatively rate their panels)p.s. the lathe has a 1hp 3 phase motor running from VFD so no harsh start spikes.

author: EEVblog
author_rank: Unknown
timestamp: May 07, 2013, 10:15:02 am
content: Quote from: NiHaoMike on May 07, 2013, 12:48:21 amHmm, so the inverter won't power the house if there is a grid power failure?I just assumed it would!

author: Joules
author_rank: Contributor
timestamp: May 07, 2013, 11:03:47 am
content: Dave, that was the whole point of our system. It's smaller because we had to factor batteries into it. I have been waiting 10yrs for a grid tie inverter that will give you an independent supply when the grid falls over. Still waiting... The best compromise would be to charge a set of batteries from your system and when the power fails you have a backup. The grid tie in the UK will eventually end in tears when the haves and have nots start battling it out over electricity costs. Plus in a power cut our lights stay on whilst the houses with large grid arrays are all in darkness, even in the day !!!The requirement of our system is that we can keep working, and it saves us money by reducing our grid dependancy. Not a FIT cheque at the grace of our Government.

author: casinada
author_rank: Frequent Contributor
timestamp: May 07, 2013, 02:31:59 pm
content: M.J. Lorton has a few videos on Solar power. Isn't that one of his areas of expertise?

author: Harvs
author_rank: Super Contributor
timestamp: May 07, 2013, 02:40:01 pm
content: Quote from: EEVblog on May 07, 2013, 10:15:02 amNope, all the protection circuitry in them is to cut the output should the grid voltage go outside spec (can't remember off the top of my head now, something like +/- 10V, +/- 5Hz.) Also, all of these current source inverters (they track the grid voltage and output an in-phase current) have a mechanism to gain frequency. That way if a suburb losses the grid tie yet the load magically happens to be exactly the same as the sum of the inverter current outputs, all the inverters will push in a positive freq direction until they all trip out. Anti-islanding it's referred to. All so no one gets hurt working on a line they believe is dead.QuoteIn West Australia, "western power", our utility that maintains the power distribution network, recently put out a press release that it believes an overhaul of the pricing system is needed. Apparently those residents that have solar systems are not buying enough power, and therefore are not contributing their fair share to the up-keep of the grid. So they want to transfer more of the up-keep charges into the yearly service fee.

author: grumpydoc
author_rank: Super Contributor
timestamp: May 07, 2013, 02:50:53 pm
content: QuoteIsn't that rather thepointof having a set of solar PV cells on your roof?

author: Harvs
author_rank: Super Contributor
timestamp: May 07, 2013, 02:59:08 pm
content: From the residents perspective yes. From the distribution utility's perspective, they still incur all the same costs of upkeep and peak demand capacity whether you buy power one day a year from them or every day. Just now they're not getting paid much...

author: grumpydoc
author_rank: Super Contributor
timestamp: May 07, 2013, 03:12:32 pm
content: QuoteAnd with feed in tarifs they're stuck with paying you, well the government is.I must admit that while I can see the sense in PV panels, especially off grid systems, and especially in sunny climates I can't understand the push for them in places such as the UK which, frankly, doesn't seem to be all that well suited to the technology.

author: jnissen
author_rank: Regular Contributor
timestamp: May 07, 2013, 05:52:58 pm
content: Congrats for pulling the trigger on the system.You said I didn't provide any detail. Correct since I don't have a single inverter system so can't give you apples to apples comparison. The only way to really determine that is to use the same panels and do an A vs. B type test. The paper I linked to did exactly that. I have done numerous comparisons of similar sized systems using PVOUTPUT.ORG. Check them out and hopefully your provider will supply an API key so you can participate on that site. Good luck with the system.

author: EEVblog
author_rank: Unknown
timestamp: May 08, 2013, 02:19:34 am
content: Quote from: Harvs on May 07, 2013, 02:40:01 pmYes, of course. I (wrongly) thought that the inverter could continue to divert the power to the house whilst disabling the mains input.QuoteThere should be a fixed "supply charge" or connection charge for everyone, and that's it. Consumption should irrelevant.The problem comes when the bloody governments either run the electricity supplier as a "state owner corporation" (i.e. "for profit"), or worse, privatise it entirely.And politician who suggests privitasting our essential utilities should be immediately removed from office and stabbed a thousand times with their own pen. Or worse, made to go get a real job.

author: EEVblog
author_rank: Unknown
timestamp: May 08, 2013, 02:22:30 am
content: Quote from: jnissen on May 07, 2013, 05:52:58 pmOh, that looks neat, will have to investigate!I do want to provide live streaming of my data to the web somehow. The Sunnyboy with bluetooth should allow me to do that somehow...

author: peter.mitchell
author_rank: Super Contributor
timestamp: May 08, 2013, 12:14:07 pm
content: Quote from: EEVblog on May 08, 2013, 02:19:34 amThe annoying thing though is, they tend to charge supply upgrade/maintenance fees, but then also increase prices and use maintenance and upgrades as justification for the price increases.

author: lemmegraphdat
author_rank: Frequent Contributor
timestamp: May 08, 2013, 10:55:55 pm
content: Quote from: EEVblog on May 08, 2013, 02:19:34 amI think that no matter what entity runs the utility the money needed to run things will always increase and all charges will still exist. You can chop them up and name them anything you want too. Supply charge or connection charge or whatever. If I understand you correctly when you say consumption should be irrelevant, do you mean everyone should pay the same no matter what amount of power they consume? If so, then doesn't that mean that the large companies will pay a lot less and you would have to pay a hell of a lot more? Maybe I misunderstand.

author: gxti
author_rank: Frequent Contributor
timestamp: May 08, 2013, 11:09:12 pm
content: Quote from: Harvs on May 07, 2013, 02:40:01 pmI've always wondered how that worked, now I know. Very clever. Is it possible to run them detached from the grid, e.g. if the power goes out?

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: May 08, 2013, 11:25:48 pm
content: I can remember playing around with polycrystalline solar cells and doing a simple shade test, about 3-4 years ago.Put one hand over a cell and you output current drops to IIRC 20% of original .I also put once put a towel over half a solar panel on a 1.5 kw domestic system, making a 10% blackout and the the output power dropped to IIRC 20% of original. Cant remember the panel type.So my experience is roughly in line with what jnissen is saying, although I heard monocrystalline panels may behave differently.If you look at a model of a PV system it would be a whole lot of small current sources placed in series, to acheive say 120V on load. If one of the current sources is not producing current, it may well all go to shit. Yes I know they have bypass diodes but that is only one or two per panel.If I was putting up solar I would make sure if possible that they get minimal shading and any shading they get all happens at the same time.In regard to the Solar Centre in Alice Springs,http://www.dkasolarcentre.com.au/flash/processmap.htmlsite 16 is giving information on panel directions.It seems you get at least 10% more energy from due north than due east or due west. This data has been collected for about 5 years, and is specific to Alice Springs but I would say that the difference would be more in Sydney as the latitude further from the equator.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 09, 2013, 06:37:13 am
content: The last time I looked into getting a solar system was Dec 2012.Quote was:12 panels (2 rows of 6), 250W/panel ==> 3KW. $3000 installed.Panels are:http://www.solarjuice.com.au/products/solar-module/trina/(I forget which inverter they quoted for.)But looking up the status of feed-in tariffs:http://www.energyaustralia.com.au/residential/products-services/solar-power/solar-feed-in-tariffsNew South Wales’ Feed-in Tariff***If your generator was not connected to the New South Wales electricity network by 30 June 2012, you will not be eligible for Solar Bonus Scheme tariff payments.***It seems that train has left. The government reached their target 300MW of installed solar, and found that with all the people they are paying 60c and 20c /KWHr, it's costing them too much. So now they won't pay anything at all for power from newly installed systems. Which means the ONLY financial payback from new systems is via reducing your consumption bill. And some very small payment you may get from your electricity provider - varies between companies.But here's the catch. Domestic solar systems are only single phase. I've never yet been able to find a 3-phase one.Which means you can only reduce your grid consumption on one of the 3 phases, and (lacking batteries) only during the daytime (on sunny days.) And most of your power consumption will typically be at night anyway. In other words, the best you can hope for is to cut down 1/3 x sunny_days/all_days x sun/night_time of your existing consumption. A quite small fraction.And then what portion of your bill is from actual consumption, vs service fees?You can bet that the service fees portion is going to keep rising. (In reaction to all the people installing solar. Someone's got to pay the amortization of all those power stations.)The upshot is, that under the present pricing model, the solar system operation time to recover installation costs is a really long time. I keep getting figures like 20 years or more. Likely longer than the system will last. So there's little _economic_ justification for doing it. But there are _other_ justifications...More notes from their site:--------The Solar Bonus Scheme provides a feed-in tariff for eligible customers with small solar or wind generators connected to the grid.As of 1 July 2012, energy retailers must contribute a minimum of 7.7 cents per kilowatt hour towards the 60 cent and 20 cent NSW Solar Bonus Schemes.*** It is possible to connect a renewable energy generator to the grid without participating in the Solar Bonus Scheme. ***EnergyAustralia currently provides a retailer-funded feed-in tariff to customers who aren’t participating in the NSW Solar Bonus Scheme and who have a system with an inverter rated at less than 10 kilowatts in size.The overall scheme started on 1 January 2010 and operates until 31 December 2016.For more details, visit the NSW Government Solar Bonus Scheme website or contact us.http://www.trade.nsw.gov.au/energy/sustainable/renewable/solar/solar-scheme/solar-bonus-scheme--------There's another catch too. If you go the 'official grid connected system, with tarrif' path, you are *required* to have an extra meter installed, to record the output of your system. And guess what? It's going to be a smart meter. And they will probably want to replace your existing mechanical meters with smart meter(s) too. These are the things that operate a mesh-connected wireless network, on a dedicated frequency, with quite high power transmitters in the meters, and a traffic-dependent variable burst transmission repetition rate. Many people are reporting really horrible health damaging effects from these things. Not to mention questions about the wisdom of giving authorities real-time access to your daily power consumption data, and also (apparently) the ability to mess with your power availability via the meter wireless network. Considering that there's no conceivable way a smart meter can do anything to help you, the consumer, and how forcefully governments worldwide seem to be pushing their installation, I smell a very stinky rat here. It can't be all just about sacking meter readers.Oh, and of course for installing the new meter(s) and the inverter, you'll have to pay for the meters, and have the work done by a licensed electrician. I found that you really have to ask whether these costs are included in the quotes you'll get for solar systems. Often they are not.After looking into that stuff a bit, I decided there'd be smart meters installed on my house over my dead body. But I can see that eventually it is likely to become a real conflict. I'd prefer to avoid that one entirely.So, my requirements for a solar system no longer fit the standard commercial model. I want a system that:* Isn't reported to the authorities. 'Grid independence' means they don't even know you have it.* It has to provide 3-phase power (I have a 3-phase workshop.)* Must be able to maintain house supply even if the grid goes down, or I throw an isolation switch.* While grid connected, it has to be able to support a proportion of my house load that can be profile-programmed, so the grid authority sees a fairly normal consumption profile. (Except I'd not be drawing as much from them as I'm actually using.)* It has to have battery storage, to support loading at night, or during long grid outages. Eventually, to just disconnect permanently.* It has to be able to disconnect and reconnect from the grid gracefully, ie must have phase & voltage locking before connect. And it must do this automatically. Whether it works by direct connection, or via a grid AC to battery DC inverter, isn't critical, though the former is more efficient.* While grid connected the system has to conform to grid safety standards, ie not try to energize a dead grid. Don't want to be electrocuting any linesmen. But while grid independent it has to just keep working, and run a clean sine wave at an accurate 50Hz, 240VAC.* While grid connected it has to monitor the sanity of the grid (phasing, voltage and frequency limits) and disconnect FAST if something weird happens. Basically an EMP or deliberate sabotage firewall. That's a whole can of conspiracy worms, no point going into it here.There doesn't seem to be anything like that available. And I wouldn't be at all surprised if that's deliberate. The government really doesn't want suburbanites to have the ability to go independent of the grid. I haven't found out yet, but I wouldn't be surprised if there's some legal obstacle to running a household completely independent of the grid in a city. I bet if you just tell the power company to come disconnect the lines, then they find you're happily living with a powered-up home without paying them anything, I *bet* there'll be some way they can make life difficult for you.Better to just not let them know, while reducing your bill as much as possible. "Hey, I'm away a lot, OK?"All of this is currently a bit moot though, since the roof aspects on my place are terrible for solar. Plenty of big roof faces, but all facing wrong ways and/or tree shading. If I covered ever feasible surface, I reckon I'd average about 20% of the ideal power output. Sucks. But I'm not cutting the trees down.Overall, anything solar I do will be more of an exercise in system evaluation for living somewhere else, someday.Btw, about roof mounting. I gather that with a tile roof there are clips that slide under the tiles and attach to the battens. No drilling holes in tiles (which you later can't get at to fix leaks, due to the solar panels.)But I haven't yet found a place that sells the mounting hardware by itself. Anyone know?For my roofs the mounting system also has to not accumulate leaf piles. Not sure how that can work.

author: EEVblog
author_rank: Unknown
timestamp: May 09, 2013, 08:44:13 am
content: Quote from: TerraHertz on May 09, 2013, 06:37:13 amThat is very cheap for Trina panels, almost too cheap.The inverter must be a no-namer.Would also be minus the meter, and probably the cheapest mounts possible etc. These cheap system like also substitute inverters, panels, and other parts with whatever they have on hand at the time.QuoteYes, it is now 6 cents kWh feed-in tariff.QuoteOnly if you have a 3 phase house, most people don't, including me.QuoteI pay $62/quarter.QuoteMy conservative estimate is 4-5 years. We'll see. By the end of the month I should be outputting some power.YMMV of course.

author: EEVblog
author_rank: Unknown
timestamp: May 09, 2013, 08:50:11 am
content: Quote from: TerraHertz on May 09, 2013, 06:37:13 amI don't believe there is. You can tell them to disconnect you.I have a recollection the same can't be said for sewage connection. They force you to pay the connection fee regardless. But I could be wrong on that.QuoteI greatly doubt it, given that all the retailers are now privatised. Disconnect from your current provider, and who's going to know to bill you now?

author: TerraHertz
author_rank: Super Contributor
timestamp: May 09, 2013, 09:32:39 am
content: Quote from: EEVblog on May 09, 2013, 08:44:13 amAt the time my objective was just to get panels on the roof, and not care much about the inverter since I figured I'd want to be experimenting with alternatives anyway. I could look up which one it was, but no point.Also, remember that was around the time the govt installation subsidy was ending. So I think the installers were probably encountering a large drop-off in business. Hence the low price. That was actually why we were looking at it then.The deal killer was that with an 'official' system, there was no way to avoid the smart meter bullshit. And the meter box is directly adjacent to the bed in which my wife's very aged grandmother sleeps when she stays with us. Now if we _wanted_ her to die, maybe we'd have got the system.QuoteI think that varies depending on your electricity company. (And damn, this whole idea of there being different private electricity companies, using the wiring and power stations our taxes built, burns me up.)It would be great to know the *real* cost of electricity generation. From the power stations, and before all the carbon tax political crap.QuoteSingle only? Quite a lot of houses have two phases. They let you have three phases if you have a big aircon, and since I wanted 3-phase for the workshop, we included a big aircon in the house design. Which we very rarely use.QuoteIt's a hard figure to pin down. For one thing the estimates of sunny vs cloudy days are suspect, since we seem to be having a long term weather shift to wetter on average. Then you have to estimate the effect of your roof orientation, likely shading profile and so on. All the advertising estimates seem to be for ideal panels facing the exact optimum direction, on a flat plane.On the plus side, we can expect grid power costs to keep rising. But how fast? Inflation plus political factors, it's useless trying to predict. I just found that making reasonable seeming estimates of panel de-rating due to my bad location, gave ridiculously long payback times.Quote from: EEVblog on May 09, 2013, 08:50:11 amI can't give references to support this, but I recall being told by someone who'd know, that anyone setting up their own permanent generation system is required to install meters on it, and the state reads the meters, and bills them - for their own power! I don't know if it's really true. Might be only for major installations.I'm cynical enough about government in general that I'd easily believe that. While you're the opposite.I've no idea how one would go about finding out for sure.QuoteThat's a good point. But it doesn't change the fact that once they *did* figure out you were doing it, if there is a legal prohibition you'd be in a world of shit. And if significant numbers of people started doing this, I'm sure the authorities would put some effort into finding them.This is something I'd really like to know either way. Since the issue of generating independent power in the city (via solar or whatever) is of great interest to me. And everyone else too, of course.

author: EEVblog
author_rank: Unknown
timestamp: May 09, 2013, 09:44:33 am
content: Quote from: TerraHertz on May 09, 2013, 09:32:39 amWhat does that mean?I hope you don't mean ELF / GSM radiation?QuoteYes, it does. But the majority in NSW are around that figure.From:http://www.energymatters.com.au/index.php?main_page=news_article&article_id=3275QuoteQuoteAFAIK 3 phase aircon have now been banned. At least in new home installations in NSW.Yes, some houses have 3 phase, but the vast majority have only single phase.

author: TerraHertz
author_rank: Super Contributor
timestamp: May 09, 2013, 10:06:45 am
content: Quote from: EEVblog on May 09, 2013, 09:44:33 amCommercial wireless electricity meters use standard GSM modules. 'Smartmeters' do not. They use an entirely different system, custom and only used by smartmeters. It's an standalone mesh network topology, that has nothing to do with GSM. Packets are routed from meter to meter, not meter to GSM tower. And the transmit power is a lot higher than GSM phones. Suggest you do some googling. Also have a look for people reporting the illnesses they've come down with when spending a lot of time in close proximity to a smartmeter (not a GSM meter), such as sleeping in a bed a few feet from a power box on the other side of a wall.Also, I've read a fair bit on the physiological basis of RF field interaction with the body, and yes there definitely are a lot of complex effects. Some of them for instance involve screwing up ion-transport via the structures through cell walls - and a lot of metabolic signaling is done by those channels.QuoteWell then, I'm glad I got in before that happened. Interesting isn't it? If people want to pay for the cables, and are paying for the power, what's the problem? If you're trying to cut down consumption, 3-phase motors are more efficient than single phase shaded pole or capacitor types.Ah! Wait, maybe this is it. I heard that while the solar power tariff was still stupidly high, like 60c/KWhr, some people were rorting the system by installing cheap solar system, then adding a gadget to draw power off the non-solar phase to their home (paying 15c/KWHr or something like that), run it via an inverter to the solar system, and so back to the grid on the phase they get paid 60c/KWHr for. Profit!Trust an artificial government incentive scheme to produce a situation like that.

author: Codemonkey
author_rank: Regular Contributor
timestamp: May 09, 2013, 10:37:24 am
content: Quote from: TerraHertz on May 09, 2013, 10:06:45 amReally ? I've worked on software for a number of smart meters. They were all using the ZigBee protocol, using modules that have a transmit power of just a few milliwatts, significantly less than that of a GSM module.Sounds like more tinfoil hat brigade bollox to me.

author: jpb
author_rank: Super Contributor
timestamp: May 09, 2013, 10:46:55 am
content: Quote from: EEVblog on May 03, 2013, 10:09:31 pmI got quite excited when I saw this, wondering how big a star you were going to use and how many planets!

author: gxti
author_rank: Frequent Contributor
timestamp: May 09, 2013, 01:54:04 pm
content: Quote from: TerraHertz on May 09, 2013, 10:06:45 amIf you know of some peer-reviewed, double-blind tests that show such things then I'd love to see them. Until then, the scientific consensus is overwhelmingly in favor of "no effect". People can and do get physically ill because they're afraid of technology, it has nothing to do with the actual RF.

author: SeanB
author_rank: Super Contributor
timestamp: May 09, 2013, 07:08:01 pm
content: Here they introduced a sewage charge, saying it would not affect the bill. Yeah right! One goes up, and the other follows, so you effectively had a 100% plus increase, as the water price did not go down, nor did the rates that supposedly covered sewage. If your property is big enough though you can go to a septic tank and soak pit ( or in some areas that do not still have sewage piping) and not pay the sewage fee, though you still have to pay the honeysucker when he comes to collect the honey when the tank is full. Do it right though and he never needs to come.

author: 4to20Milliamps
author_rank: Regular Contributor
timestamp: May 10, 2013, 03:14:32 am
content: Quote from: gxti on May 09, 2013, 01:54:04 pmCareful.....the "off topic cops" will be along shortly to bust youI'd say if any of the people complaining of symptoms from a smart meter.....or any other meter that's several feet away, own an electric blanket, then they might lose their case in court.Interesting stuff for anybody that's interested:http://books.google.com/books?id=PVnwAAAAMAAJ&dq=harmonic%20oscillation%20electrostatic%20field&pg=RA3-PA59#v=onepage&q=harmonic%20oscillation%20electrostatic%20field&f=false

author: jnissen
author_rank: Regular Contributor
timestamp: May 17, 2013, 06:04:37 pm
content: Hows the system install going? Any update?

author: Precisiontools
author_rank: Regular Contributor
timestamp: May 18, 2013, 08:51:38 am
content: Pity I didn't see this thread earlier. Did you take a look at the Selectronics inverters Dave? The SP Pro? Nice designs, Aussie made and I am pretty sure you can isolate them from the mains (street side) to continue supplying your house. If not, adding a battery will do it for you.Yes the SMA stuff is nice and has some nice features, it would be a hard call for me.

author: EEVblog
author_rank: Unknown
timestamp: May 18, 2013, 09:03:36 am
content: Quote from: jnissen on May 17, 2013, 06:04:37 pmIt has to be approved by my energy supplier (Origin) first.

author: EEVblog
author_rank: Unknown
timestamp: May 18, 2013, 09:04:19 am
content: Quote from: Precisiontools on May 18, 2013, 08:51:38 amNever saw those, no one offered them.

author: Precisiontools
author_rank: Regular Contributor
timestamp: May 18, 2013, 10:18:04 am
content: I know its probably all too late now but...http://www.selectronic.com.au/sppro/

author: EEVblog
author_rank: Unknown
timestamp: May 18, 2013, 10:27:09 am
content: Quote from: Precisiontools on May 18, 2013, 10:18:04 amSounds like you need the batteries.Not worth it for me, power failures are very rare here.

author: Lightages
author_rank: Unknown
timestamp: May 18, 2013, 06:40:06 pm
content: Yeah, if you don't have a need for frequent power backup then a battery system is a big expense. For very infrequent and short term power backup a generator is much more cost effective and less wasteful.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 18, 2013, 07:13:08 pm
content: Quote from: Lightages on May 18, 2013, 06:40:06 pmMain problem with a generator is that unless you use it on a regular basis, it probably won't work when you do need to use it. Cycling a generator every few weeks just to get around that problem seems a bit wasteful.In cold climates, CHP can be a very viable idea as the primary source of hot water and/or space heating, as well as supplemental and backup power. An induction generator can operate either grid tie or independently.More in general, a common standalone inverter would work nicely for backup power. No point in buying a whole generator (at least for most home users) when there's already one under the hood of your car. (On the order of 1kW for a standard car, several kW to a few 10s of kW for a hybrid.) 1kW will easily run a refrigerator, small window A/C (will probably need a 1.5kVA or larger inverter to start, with the peak being supplied by the battery), and countless electronic devices.

author: Lightages
author_rank: Unknown
timestamp: May 18, 2013, 08:19:04 pm
content: Running a car just to charge a battery is also very wasteful. A running car will use more energy in just idling for a few hours than a generator would use to run 1kW for a day, actually doing something. Car batteries are also not for any kind of deep cycle use, they die very quickly doing that.Anyway, the point is if you do not have frequent power failures, then a battery backup system is a huge expense that goes mostly unused. Batteries have a 10 year shelf life maximum, so they also need to be changed at least that often, and if used to any extent then between 5-7 years.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 18, 2013, 08:59:09 pm
content: Quote from: Lightages on May 18, 2013, 08:19:04 pmIf it's really very infrequent, it ends up being less waste than all the "test runs" you'll do on a standalone generator. (Now if you do use it regularly, one of those Honda units with integrated inverter or a CHP system would probably be appropriate.) And with a hybrid, fuel consumption is competitive with the Hondas.http://priups.com/others/Doug/index.html

author: Precisiontools
author_rank: Regular Contributor
timestamp: May 19, 2013, 08:45:46 am
content: The theory is to use both!You have a small battery bank to protect you from brown-outs and small scale black outs (a few minutes or so). Smart inverters (like the SP Pro) will know that the mains has been dropped and will supply the household needs via the solar panels, unused energy can be diverted to the batteries if it is needed. If the power is dropped at night (or during a low solar period) and the disconnection lasts longer than a pre-determined time (depending on the load being drawn, and the capacity of the bank), then the inverter can auto start a generator, sync with the inverter and transfer the load without it even being obvious to the user. When the mains comes back up, the gen turns off, inverter syncs back to the mains and everything goes back to normal.

author: EEVblog
author_rank: Unknown
timestamp: May 19, 2013, 08:56:13 am
content: Quote from: NiHaoMike on May 18, 2013, 08:59:09 pmHere it's maybe once a year at best, and a long outage would be an hour or two tops, but mostly they are much shorter.I can also go 5 min down the road to the lab..So any backup system is just a waste of money here.I don't recall a single blackout at the lab since I moved in.

author: jnissen
author_rank: Regular Contributor
timestamp: May 20, 2013, 05:57:45 pm
content: Yes complete off the grid solutions in an area supplied by the grid is a bit of a overkill. Grid tie has a low overhead cost and actually does what you want - reduce your energy bill!I have Enphase inverters so I can monitor production per panel.http://www.enphase.comThey are a grid tie inverter and you can't do a battery backed solution easily. There is a system that will work with the micro-inverters that have a large battery bank but they are very expensive and very seldom used. If I have power out for a few days I use a gas generator. I had that problem a year or two back. Wildfires caused the grid to be cut for about three days. I kept my refrigerator and freezer alive with the generator and didn't lose anything.