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which PV system?

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Started 2 years ago by greensmonster
Latest reply from Sunshine

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greensmonster
Member

Hi everyone

This is my first post here, so be gentle! Looking forward to having a bit more of a look around - what an awesome resouce - I wish I knew it was here earlier. You are all very inspiring.

We are looking at spending some $ on reducing our carbon footprint here in suburban Perth. We currently have an electric storage HW system which is ancient and will probably need replacing shortly anyway, so are looking at doing this as well as installing a PV system. We are approved for the $8000 rebate (luckily got the paperwork in before it was reduced), but I am completely bamboozled by sales hype and technicalities.

Would really like your advice about a small PV system - say 1-2kWh. We have a north facing roof which can fit 18 of the 60W kaneka thin film panels on it. The west facing roof is partially shaded by mulberry trees which are only about 5 years old (so they'll get bigger). Mulberries are really semi-deciduous here - only lose all their leaves about 1 min before the new buds burst.

Thanks xx

Posted Friday 11 Sep 2009 @ 7:55:36 am from IP #
Benny
Member

Welcome Greensmonster. I'm in Perth too and got the Kaneka panels through SolarShop and am very happy with it. We got a 1.4kW system as that fills all our available roof space - and the budget!
18x60W panels is only 1080W so if you want to make better use of the roof space you could go for the more efficient single crystal types. I went for thin film as the embedded energy payback is so much shorter and we have the roof space to accomodate the extra area needed.

Its hard to give recommendations on which systems/suppliers are good as most people only ever deal with one supplier. I was happy with Solarshop but haven't really heard of any "Bad" ones.

Posted Friday 11 Sep 2009 @ 9:27:33 am from IP #
munter
Member

Hi Greensmons,
If you're running resistive electric hot water then your first action should be to replace that with one of the more efficient forms of water heating. An electric heater uses a large amount of electricity - possibly more than a 1kW solar panel system would produce!
Also think carefully about how you are going to boost your solar hot water. Gas is more expensive to install but cheaper to run. Good solar installations require minimal boosting in which case electric boosting might be a reasonable trade-off.

It isn't really as sexy but reducing consumption of electricity is typically more cost effective than producing your own renewable electricity. The net effect is the same. Both are worthy goals though.

Posted Friday 11 Sep 2009 @ 10:51:10 am from IP #
greensmonster
Member

Thanks Benny & Munter!

Good to know that you are happy with your system Benny. How many units is it producing at the moment? I'm aware of the relatively low embedded energy in the thin film and that's the main reason for heading towards the Kaneka, as well as complete ignorance of a comparable alterative

We are going to replace the HW system definately. I know getting rid of that thing will reduce our consumption a heap. Luckily we are a bit feral and don't shower everyday, especially in summer when we're at the beach everyday, so that saves a fair bit of electricity!

We also need a heater - our house is lovely and cool in the summer as we have planted heaps of trees, have lots of tiled areas and are so close to that beautiful sea breeze - we never use the old wallmounted aircon, but heating is an issue. We have awesome insulation, but no curtains, so they're on the list. We only have a little bar heater, which sucks the power - I wouldn't use an unflued gas heater. So we are thinking of installing a small split system a/c for the living area for the cold nights.

We are already approved for the $8000 rebate, so feel that we 'should' use it because it's there. We were tossing up between that and the solar HW until they cut the HW rebate. If only gov thinking made any sense!

I have also been looking at the plugs that you put on the powerpoints which have a remote de-activation switch that you hit when you go to bed and it automatically turns everything with a plug on the switch off (I know that doesn't make sense, but YKWIM!). Apart from that I think we are struggling for ways to reduce our consumption of energy for the house.

So if anyone has info on thin film panels and inverters that they feel are better than what solarshop offer, I would love to know.

Posted Friday 11 Sep 2009 @ 12:56:18 pm from IP #
wandifred
Member

Hi Greensmons,

Good to see another solar adopter from Perth. I have a 1.5kW system from Conergy installed on my roof and will be getting a 3.15kW system added this Tuesday weather permitting. Due to the limited roof space I have facing north, I chose monocrystalline panels from Sun power 225W which, though more expensive than other panels, gives me the best space saving so I can add more later if I wish. My total capacity will be 4.68kW. This coupled with "Smartpower" will hopefully send my electricity bills to the bin. I live in a special rural area south of Perth and tend to use more electricity than you standard household hence the larger system.

I purchased a set of remote plugs that you described and I find them excellent. They come in a pack of 3 with a wireless remote and makes turning off all standby appliances a breeze. Lets face it, crawling under the TV cabinet to turn off the powerpoint for the rest of your life requires a special dedication. Switching all 3 powerpoints off in the comfort of your lounge chair doesn't. As the remote is wireless, all appliances upstairs get switched off too from the same chair. I bought mine from Sustainabode a company based in Kwinana but I'm sure they can be obtained from other sources.

Cheers,
Fred.

Posted Saturday 12 Sep 2009 @ 3:56:06 am from IP #
greensmonster
Member

Thanks Fred, we are near freo, so not far from you.

Great to hear the remote switches are good will definately get some.

Could you tell me how many units your system is producing at the moment? Just interested to hear if the sales pitch does in fact reflect reality. Did Sun Power install your initial system?

Cheers

Posted Saturday 12 Sep 2009 @ 4:16:40 am from IP #
wandifred
Member

As I haven't had my system running for very long I can't really say how much my system will produce annually but there is a calculation that can be used to give you a rough idea. A 1000kW system in Perth should produce around 5 units of power per day on average. So 1080W should produce about 5.4 units a day. My 1530W should produce about 7.65 units a day. I've only seen Winter and Spring months so I can't really say what my system can produce on a nice Summer day. Of course it appears that as the panels get past their preferred operating temperature, production reduces also but I haven't seen a day like that yet. I took my info from the Energymatters website so please correct me if my info is wrong.

What really is paramount is the amount of shading that your site receives. My system was severly hobbled by some light shading from a young gum tree. Imagine my horror when I went to check my inverter output at the moment it breathed life to see 100W with the the sun shining! The next day I removed the tree and 100W jumped to 800W+. I have since removed all the problematic trees to open up a clear area and now energy production is only reduced by clouds. Remember that only one monocrystalline panel needs to be shaded to bring the whole lot down but for power to size ratio, they can't be beat.

My first system was organised through Solar Harness as they are the Perth dealer for Conergy I believe. Conergy badges it's panels and inverters but they say they use top quality components. The Conergy WR2300 in my system is made by Fronius for example. My second system is being installed by Energypak Solar, a Father and son team. It will incorporate 14 SunPower 225W panels through a SunnyBoy 3800 inverter. Though perhaps it could be a bit risky dealing with a small company, I enjoy the far more personal service I receive as I am only dealing with one person who doesn't live that far from me.

Cheers

Posted Saturday 12 Sep 2009 @ 7:17:37 am from IP #
rockabye
Member

My 1020Wp monoxtal system facing NW has produced 365kWh in 87 days or 4.2kWh per day. Only in the last couple of weeks has it exceeded 5kWh/day on a couple of occasions.

Had the same tree issues early on but these are now resolved. Will be impressed if it actually does average close to 5k/day but suspect it will be a little less. Time will tell.

Posted Saturday 12 Sep 2009 @ 7:48:35 am from IP #
wandifred
Member

Hi rockabye,

My 1530kW mono system has produced an average of 5.22kWh since activation in July. Summer had better bump up the figures or the energy returns might need to be ammended.

Posted Saturday 12 Sep 2009 @ 8:06:32 am from IP #
rockabye
Member

These are all winter numbers so theoretically the upcoming longer days will produce the extra we need. Trouble is we have a wet season here in Rockhampton so this will reduce averages also.

Not that it really matters as our overall energy use after solar and various energy efficiency measures is still trending down. Things like the remote switched outlets are on my list as well.

Cheers, Brian

Posted Saturday 12 Sep 2009 @ 8:26:37 am from IP #
greensmonster
Member

Thanks Brian & Fred good to know.

We had modern give a quote and they were suggesting 18kWh/day in summer... would love to know if that ever happens and on how many days...

cheers

Posted Saturday 12 Sep 2009 @ 11:12:40 am from IP #
wandifred
Member

You haven't mentioned the actual size of the system quoted? The panels work a bit like a generator powered by sunlight. I'm not sure if the maximum rated power of the panels is achievable when the sun is at optimum levels and angles but they start off slow, build up to a constant production for a while (cloudless days) and then power wanes as the sun goes down. Factor in a loss of energy production on the hot days into the equation and you get the picture how messy daily power ratings can be. One day does not your bills pay. Ask them for a yearly output...it's how your panels perform when there isn't much sun that needs to be considered.

cheers

Posted Saturday 12 Sep 2009 @ 3:17:24 pm from IP #
rockabye
Member

Greens, Fred

I've put a few bits & pieces about my system on a web page. About to upload the data for the first 90 days this Wed but other info may be of interest.

All members with webpages have their name highlighted in green. Click on the 'rockabye' name at the left of the post to go to the page.

Posted Sunday 13 Sep 2009 @ 1:53:31 am from IP #
Sunshine
Member

I've been getting 18.4kWh per day this week..System size is 3kW poly.
Last summer peak attained was 18-19kWh per day, this summer will no doubt reach 20kWh maybe more as I've trimmed some trees killing afternoon production.
Will wait and see..

Posted Sunday 13 Sep 2009 @ 9:41:55 am from IP #
greensmonster
Member

Fred, the size quote was 1kWh system - that's right! 1 (as in one) kWh system.

Thanks rockabye - will check later in the week.

Posted Sunday 13 Sep 2009 @ 2:43:47 pm from IP #
Sunshine
Member

greensmons,

Is Modern quoting 18 kWh per day from a 1kW system?
Depending where you live in the country a 1 kWh system will produce between 4-6kWh per day on a good day.
If they are quoting 18kWh, they would be quoting more than likely peak production from a 3kW system, not average production.

Posted Sunday 13 Sep 2009 @ 11:09:39 pm from IP #
greensmonster
Member

That is correct!

18kWh per day summer for a 1kW system! They are also quoting an average of 5.2kWh per day annually, but stress that this is underestimated to be on the safe side etc etc. and you can get up to 18kWh/day in summer blah blah blah... I think it is really wrong as many people would believe it.

All calculations were extrapolated taking into account that you use NO electicity during the day and therefore are paid the tarif for the sum total of energy produced (currently the tarif is non existent here anyway, so it was a hypothetical tarif of 1:4).

Grrrrrrr

Posted Monday 14 Sep 2009 @ 1:55:19 am from IP #
munter
Member

If you're going to pull 18kwh out of a 1kw system then you're going to need 18 hours of full strength sunlight to do it! The 18kwh figure seems a little optimistic.

Posted Monday 14 Sep 2009 @ 3:17:22 am from IP #
rockabye
Member

Another 1kW system located about 15km away has averaged 5.065kWh/day in the first 92days. This is a Thin Film type with 1000Wp made up of 10 X 100W modules. The same model inverter is installed. It is performing about 20% better than mine.

This is a valid comparison of similar sized systems, in the same location, using different module types. Weather conditions would have been almost identical.

Some of the differences can be explained by installation factors and module type which I'll put up on my website.

Posted Monday 14 Sep 2009 @ 3:30:07 am from IP #
Sunshine
Member

greensmons,

As Munter has pointed out, a 1kW system would need 18 hours of midday type sunshine to produce anywhere near 18kWh per day. Typical yearly average would be 4-5kWh per day for a 1 kW system.
I know Brisbane's average is supposed to be 4.2kWh per day per 1kW system as an example. Anything more than that is a bonus.
There are alot of variables with where you live in Australia, panel type, inverter efficiency, length of wiring, panel type, tilt and angle etc etc.
I'd be wary of company's who are quoting figures way higher than this..

Posted Monday 14 Sep 2009 @ 7:25:30 am from IP #
wandifred
Member

I checked the Modern website which can be accessed at;

http://www.modernsolar.com.au/power/our-systems.aspx

Looking at the power production figures quoted on their web their systems might produce an average of; MOD1000(990W) - 3.56UPD, MOD1500(1485W) - 5.48UPD, MOD2000(1980W)- 7.4UPD and MOD3000(2970W) - 10.95UPD based off their website yearly output figures. UPD means units per day and is the equivalent of kW/h.

They use 165W panel of unknown origin with a Fronius inverter. The image says "images for illustration purposes" but I didn't see "overseas model shown"

Hope this info helps you make an informed decision.

Posted Monday 14 Sep 2009 @ 9:17:52 am from IP #
Sunshine
Member

Looks like Modern's figure are quite conservative. I suppose by being conservative, the website will cater for every location in Australia, without ever overstating the figures.
I'm sure there is a website out there somewhere which gives out the number of full sun hours per day average per capital city.

Posted Monday 14 Sep 2009 @ 12:22:29 pm from IP #
ec175
Member

Anyone know anything about this company?

http://www.solarhut.com.au/product_1.5kW_specs.html

Specs look like this:

"# Inverters 1 inverter(s)
No of Modules 8 modules
Gross Area 10 m²
Price Before Rebates $13,600
Solar Credits Zone 3 $5,580
RECS $1,395 (31)
Total Rebates $6,975
Solar Hut Discount $2,125
Total Discounts & Credits $9,100
Customer Cost $4,500
SMA SB1700 Sunnyboy Inverter specs:
Dims (mm) 434x295x214
Vmin 150 Vdc
Vmax 400 Vdc
Imax 12.6 Adc
Pmax In 2100 W
Pmax Out 1700 W
Warranty 5 yrs
Max PV/inv 12

8x 190W Suntech poly-Crystalline Solar Panels with 25 year warranty (or equivalent)
SMA Sunny Boy 1700 inverter with 5 year warranty
Aluminium / Stainless steel mounting system
Full grid connect installation by BCSE accredited electrician on your home
New Solar Credit discount and processing
RECs discount and administration
Onsite training and system demonstration
No income tests required and can be installed on any property *
Available to all Australian residents, businesses and companies *
Installation available Australia wide #
Installation within 8-12 weeks (if availability allows) of any approval process that may be required
10 m² on your roof
All Extra Charges
- If you have a tile roof add $100
- If building is double story add $200
- Supply of new power meter not included"

I understand that the Suntech panels are regarded as the best of the Chinese brands however the vendor seems to reserve the righ to substitute (or equivalent) which could be a worry?

Also, I see that they exclude a new power meter. Is this usual and how much extra do you generally need to allow for this? I guess this is supplied and charged by the power supplier?

Posted Monday 14 Sep 2009 @ 12:22:50 pm from IP #
Sunshine
Member

ec175,

All quotations exclude new power meter.
I rang Integral Energy(when I was with them) and they said $300 for a new power meter.
However they don't install them, they are just the retailer.
Energex (the wholesaler)went out and didn't charge me.
The solar installation company told me a new power meter doesn't cost anything, so maybe check with the solar company.

Posted Monday 14 Sep 2009 @ 1:32:29 pm from IP #
greensmonster
Member

Thanks for the responses

We have found an independent installer... I know, a risk, but one I think we're willing to take.

So we are now looking at Sungrid panels with either a Kaco inverter or an Orion inverter. Comments very welcome.

Posted Wednesday 28 Oct 2009 @ 5:13:44 am from IP #
ghostgum
Member

You said "We are looking at spending some $ on reducing our carbon footprint here in suburban Perth."

Note that buying a PV system and selling the RECs does not reduce your carbon footprint, but instead allows someone else (the end purchaser of Green Energy) to reduce theirs.
Have a read of this article:
http://www.ata.org.au/renew/renew-popular-articles/dont-wreck-those-recs

Posted Wednesday 28 Oct 2009 @ 5:30:22 am from IP #
Sunshine
Member

I look at REC's in a different way.
I view REC's as a discount to purchasing a system.
In the end, by having solar panels on your roof, it will mean less coal needs to be burnt to generate that power elsewhere in a power station.
It doesn't matter where the carbon is reduced, it is still reduced. We all live on the same planet.

Posted Wednesday 28 Oct 2009 @ 6:59:40 am from IP #
Sunshine
Member

ghostgum,

But if no-one installs solar PV or wind power in the first place, then there would be no green power to sell to consumers.
So really the provider of the green infrastructure that is making a difference to the carbon footprint, not the end consumer.
I suppose its a case of what came first, the chicken or the egg..
Technically speaking though, unless the consumer who pays extra for green power lives next door to solar pv or wind power producer, they are getting black power delivered to their premises.
Electricity flows to the path of lowest resistance so for example my excess power during the day, gets fed to supply the neighbouring houses in the street, whether they have signed up to green power or not.
By signing up to green power, you can't order electrons to come from a green power source, electrons will flow to where the path of lowest resistance.
So really the green power consumers are the premises located adjacent to green power suppliers. By buying green power doesn't necessarily mean you are getting green power at your premises as electrical electrons cannot be directed to specific addresses like IP networks.

Posted Wednesday 28 Oct 2009 @ 9:53:31 pm from IP #
ghostgum
Member

Sunshine,

As I understand it, the power companies are required by government regulations to buy a certain amount of renewable energy. People buying green energy help this, by paying a premium rate to contribute. If nobody bought green energy from the power companies, then the power companies would still have to source renewable energy because of government rules. If lots of people bought green energy, then it could exceed the government mandated minimum, and so the power company would have to buy even more green energy. The latter is good because it encourages the power companies to be more sustainable.

If you put solar panels on your roof and sell the RECs, then you are helping the power company meet their existing target. If people didn't put solar on their domestic roof, then the power company would need to buy power (and the associated RECs) from commercial wind or solar power systems. Should you subsidise the power companies to meet their mandatory renewable energy target, or let them buy it at commercial rates from commercial generators? If you do sell your RECs then it is likely that you are making no impact to the overall amount of renewable energy - you are just helping the power company to meet the target. If you don't sell your RECs then your rewewable energy is in addition to the mandated targets.

In any case, it's your choice whether to sell RECs or not.

I'll mostly ignore the argument about delivering electrons from green power sources, except to note that AC distribution makes this a silly argument.

Posted Thursday 29 Oct 2009 @ 12:22:17 am from IP #
Sunshine
Member

ghostgum,
"If you do sell your RECs then it is likely that you are making no impact to the overall amount of renewable energy "
That statement makes no sense, if a person installs wind or solar power system, then the amount of renewable energy produced in the country is increased by the capability of what that system can produce.
RECs has no relevance to the amount of power a wind or solar power system can produce.
The point I was trying to make was that people buying green power aren't reducing their own carbon footprint, they are reducing the carbon footprint of the power company buying the RECs certificates from wind or solar power producers.
The power companies don't surrender the RECs certificates to green power consumers.
Buying green power doesn't mean you will be supplied with green power, unless you just happen to live next to a green power producer, which in that case you are receiving green power whether you want it or not.
It's like our water supply, we have no control of where the water is sourced from.

Whilst I support the buying of green power, it is only available to purchase, because of the green power producers providing the infrastructure in the first place, not the other way around.

Posted Thursday 29 Oct 2009 @ 2:34:39 am from IP #

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