Solar power inverter sizing.

[jatz76]

I've just been re-reading the Nuenergy terms and conditions. The deposit is now $1000 which is good. Also, you can specify that you do not wish to sell them the REC's but have to pay them $800. This sounds like a good deal as the value of these is likely to go up.

[SystemRat]

Ok I’ve found the detail of the smart meters to be rolled out across Victoria and they can read both import and export of power and are remotely readable.

I don’t know what the roll out time table is but it cost a friend $250.00 for a meter upgrade so I might wait till they roll it out if it’s not too far off.

The down side is a news paper report mentions the metering cost will rise from $22.00 to $90.00. That was in 2006 so I guess it will be more now.

The two politicians involved do not inspire me that that customer value is there concern. Mr how to vote and Mr Brimbank.



PDF of Victorian Smart Meter specs

[Joey]

A question. Do you have to sell excess power to the grid ? Personally I would rather waste it than sell it for bugger all for the power companies to sell at full price to someone else ( if I am reading it correctly )

Yes you do , this is a big part of the reason you get the 8K subsidy , when the installation is complete you also have to include the verification letter from your power company that the system is connected.
The System has to stay connected and in place for a minimum of 8 years from the date of completion otherwise people would be getting these systems and selling them off to pocket the 8K.
At very worst you are selling the power back at the same price you are paying less GST so you aren't in effect selling it for money in your pocket you are just reducing your billable amount of units you normally pay for , which means less out of you pocket.

Wasting excess would defeat the purpose of setting up the system to begin with , not only that you are losing both ways by throwing away what you make and paying for the power you use while your watching the excess get wasted

[Joey]

I was wondering about that too. By design the grid connect solar inverter must have mains power present to run as a safety feature for linesmen so you’re not pumping volts on to a line they believe is isolated. There are other solar inverters which are for standalone systems but these inverters and by extension system are not covered by the grant.

The feature you are talking about is called anti-islanding , This is selectable parameter ( not end user selectable ) It is designed to detect Voltage and Frequency within a selected range for each given State / Country .
EG: if Grid Voltage falls below 206V or above 264V the inverter will disconnect from the Grid , it will then monitor Grid until all are parameters are met again and stable before it reconnects.
For Australian Compliance the conditions are detailed in AS4777 .

One thing I am puzzled by is effectively you have two power sources one being the power companies supply and the other your own solar generated supply. Both are around 240 volts AC effectively you putting both in parallel so when you use electricity the load will draw from both sources equally. Thus you’re perhaps not getting to use 100% of your own power and a part of your power is flowing out to the grid to help run other users equipment.

Yes both are exactly the same voltage so basically they become one supply , if you are drawing 500W in your house and your solar is producing 500W there is zero import and zero export , your meter will read Zero , if you are still producing 500W but using 2500W in your house you are importing 2000W.
It makes no difference if you are using the power you make or the power from the grid , Keep in mind your solar system is connected on the load side of your meter so your house will use everything you are producing and only in effect "spin the meter backwards" ( when your load is less that what you are producing ) The average house with a 1KW system will rarely export anything to the grid.

Using a smart power meter and selecting smart tariff is a totally different thing where you export power at about 3 times the price you pay during peak and only use during off peak when it's about a third the price , effectively using your 1KW system to produce 3KW of usable power in off peak periods.

I recently had someone from the power company call around to check out the meter seems they are going to replace them all with smart meters that can be remotely read. I asked does this mean they will also be able to record feed in but the guy did not know. I will try and find the answer to that as it will save me paying for a new meter.

Yes they can read feed in , times , units , import / export / tariffs times etc , like a mini computer these things
Be great if someone comes up with a wireless method to read these on your home PC.

[Joey]

I'd think that as its connected to the grid you won't be able to stop it feeding the grid. Maybe there is a software option on the inverter to not allow it? I'm not sure what would happen if you didn't upgrade your meter. Some meters only read the used power from the grid but I'm not sure if they would stop the grid being fed?

No there are no software options that the user has access too.

You don't have a choice about the meter , power companies and part of the grant stipulate a grid feed system must be connected to a smart power meter.
The whole process is tightly monitored and governed so there are no shortcuts , You need power company approval to get the gov grant , this means you have to already have a smart meter installed , if not installed and commissioned at the time of the solar system installation you dont get the certificate of completion from the power company or the installers which you need to send to the gov to get the grant.

[admin]

Yes you do , this is a big part of the reason you get the 8K subsidy , when the installation is complete you also have to include the verification letter from your power company that the system is connected.
The System has to stay connected and in place for a minimum of 8 years from the date of completion otherwise people would be getting these systems and selling them off to pocket the 8K.
At very worst you are selling the power back at the same price you are paying less GST so you aren't in effect selling it for money in your pocket you are just reducing your billable amount of units you normally pay for , which means less out of you pocket.

Wasting excess would defeat the purpose of setting up the system to begin with , not only that you are losing both ways by throwing away what you make and paying for the power you use while your watching the excess get wasted

It wouldnt defeat the purpose to me because the only purpose to me is to save myself money. Saving the planet and enviroment is not my purpose , nor is selling my power to a company for a small amount so they can on sell it for profit.

So I would presume that without claiming the subsidy that there is no way for the government to force you to connect to the grid ?

[jatz76]

Using a smart power meter and selecting smart tariff is a totally different thing where you export power at about 3 times the price you pay during peak and only use during off peak when it's about a third the price , effectively using your 1KW system to produce 3KW of usable power in off peak periods.

Joey,
From what I understand you have to install a smart meter with the solar system. Is that correct?
This does not mean that you are automatically on a smart tariff?
Would being on a smart tariff work if the owner was at home using some of the generated power (assuming that not all generated power is being used up so some can be fed back into the grid)?
Cheers

[Joey]

It wouldnt defeat the purpose to me because the only purpose to me is to save myself money. Saving the planet and enviroment is not my purpose , nor is selling my power to a company for a small amount so they can on sell it for profit.

So I would presume that without claiming the subsidy that there is no way for the government to force you to connect to the grid ?

Of course if you don't want the subsidy you can do what ever you want with it , but remember you have to somehow generate $8000 worth of your own power before you save a cent.
Technically I don't know how it would even be possible to waste excess solar produced power , because for the system to work it has to be connected to the Grid , in order to connect to the grid you have to agree to sell excess back to the supplier.
You can't rely on Solar like you can the grid ,within seconds it can go from 30W to 1000W , most of the time it's constantly fluctuating depending on the weather conditions and time of the day , the grid basically becomes a filter capacitor to make it usable.

[Joey]

Joey,
From what I understand you have to install a smart meter with the solar system. Is that correct?
This does not mean that you are automatically on a smart tariff?
Would being on a smart tariff work if the owner was at home using some of the generated power (assuming that not all generated power is being used up so some can be fed back into the grid)?
Cheers

Yeah sorry the tariff option is your choice , smart power tariffs really require a complete change in the way you use your power , it's best suited to people that are at work all day and their usage is outside peak periods.
If your usage often exceeds what you produce during the day , smart power isn't a good option.

[SystemRat]

This will be interesting as I work from home so things like washing machine and dishwasher are run during the day where as when I was a fully fledged member of the rat race in an office all day such things were done at night when I got home from work. Prior to working from home I left the PC on and a radio going to give the impression someone was here. Both these things are the same now except I am listening to the radio. My average power usage per day is 16 KW. I wonder what the solar will do to the bill.

[jatz76]

Two things I've just found out. The panels used by NuEnergy and Ecovation (CEEG panels) are only 14% efficient. This is pretty much at the bottom end of panels. Most are around 15-16%. Some get as high as 21%. Guess you get what you pay for!
Beyond Building have changed their panel to TaiZhou Sopray SR05-170. Not much info on these. I did find a data sheet but it doesn't say efficiency of the panel.
I'd assume all these free solar systems use cheap Chinese panels that are not very efficient.

[admin]

Ok , a bit more reading has shed more light on it for me and I think I understand it a bit better. My inlaws have full solar power which is what I thought this was hence my confusion.

As I see it :

They only work during the day if the sun is shining , should you generate any more power than what you use during the day it gets fed in to the grid as there are no batteries to store your own excess power with these systems unlike traditional solar power. At night , you run off mains power. If there is a power outage , even if its during the day , you have no power. If its not sunny or its night time , you have to buy power just as you are now. Its realistically a 12 hour system.

To me it seems the main beneficiaries of this system are the power companies and the government. The power companies are using consumers because there are no power storage facilities for consumers to harness what they collect and any extra power made during the day is taken by the power company to be sold off at a profit while after paying you less. The government as always tries to come up smelling roses with the greenies.

One question I am interested in though....can you transfer REC's to other individuals ? It seems they are effectively a share or commodity and can be resold ( by companies at least )

[jatz76]

One question I am interested in though....can you transfer REC's to other individuals ? It seems they are effectively a share or commodity and can be resold ( by companies at least )

I'm not sure about being able to transfer the REC's but you can sell them. You first have to lodge a application form with the gov to receive a certificate saying you own X credits (for a 1kw solar system it equates to 22 credits). After you get them you can sell them on to other companies. If you search for REC's on the web there are plenty of companies that will buy them. I don't have a clue what you'd get for them. Considering the solar companies are trading the REC's you sign over to them for $800 each one is worth $36. NuEnergy is good in that you can opt not to sign over the REC's to them but need to pay them an extra $800.
From July 1 the gov is changing the solar scheme where instead of paying $8000 toward the solar kit, they are multiplying the value of the REC's by 5 times. You then trade/sell them to get your rebate. From what I gather, the current price for REC's is not high enough to supplement the current $8000 scheme. So your better off buying one now under the old system.

[mate]

A question. Do you have to sell excess power to the grid ? Personally I would rather waste it than sell it for bugger all for the power companies to sell at full price to someone else ( if I am reading it correctly )

that is a ridiculous thing to say, putting your home on the solar grid is NOT about you saving money.

These 1kw packages will do little to most households electricity consumption, most homes may be luck to save 15% off their power bills.
This system is about ALL doing their bit to slow down global warming and taking electricity consumption on and trying to ensure we do not need to increase dirty coal fired power generators, or in fact making a need to build a nuclear power plant.

If all Australian homes, even those in Tasmania had a 1kw system, businesses would benefit with guaranteed peak demand, and maybe cheaper costs which will help business and our environment will benefit in the long run.

[z80]

that is a ridiculous thing to say, putting your home on the solar grid is NOT about you saving money.

These 1kw packages will do little to most households electricity consumption, most homes may be luck to save 15% off their power bills.
This system is about ALL doing their bit to slow down global warming and taking electricity consumption on and trying to ensure we do not need to increase dirty coal fired power generators, or in fact making a need to build a nuclear power plant.

If all Australian homes, even those in Tasmania had a 1kw system, businesses would benefit with guaranteed peak demand, and maybe cheaper costs which will help business and our environment will benefit in the long run.

You need 4 Kw + of panels to do anything that isn't just a govt subsidised rort by installers at the moment.
The Govt realizes this and is forcing the utilities to pay you THREE times what they charge you in $$$ per Kw...60 cents versus 19c from memory.
So you effectively get 3kw of money generation.

Sanity-the only reason I feed to the grid is because I am sick of replacing $4000 worth of batteries every few years.
I effectively use the Grid as a money battery.

And...wait for it...you will soon get paid more for feeding PEAK power onto the grid during the day, and you will be charged less for your nighttime off peak power.

The new smart metering is facilitating all this.

[admin]

that is a ridiculous thing to say, putting your home on the solar grid is NOT about you saving money.

I hate to be the bearer of bad news to you , but not everyone hugs trees and sings Kumbuyah my lord. Do you seriously think everyone will just do it out of the goodness of their hearts ?

These 1kw packages will do little to most households electricity consumption, most homes may be luck to save 15% off their power bills.
This system is about ALL doing their bit to slow down global warming and taking electricity consumption on and trying to ensure we do not need to increase dirty coal fired power generators, or in fact making a need to build a nuclear power plant.

I would prefer nuclear and its many benefits. Unfortunately we have a government stacked with greenies.We dont ALL have to do jack shit. We are not talking about a compulsory scheme.

If all Australian homes, even those in Tasmania had a 1kw system, businesses would benefit with guaranteed peak demand, and maybe cheaper costs which will help business and our environment will benefit in the long run.

I doubt it would be worthwhile in Tasmania which is why many have heat pump systems instead of solar hot water because there isnt enough sunshine. Heat pump water services use the ambient air temperature instead of sunlight.

[SystemRat]

Two things I've just found out. The panels used by NuEnergy and Ecovation (CEEG panels) are only 14% efficient. This is pretty much at the bottom end of panels. Most are around 15-16%. Some get as high as 21%. Guess you get what you pay for!
Beyond Building have changed their panel to TaiZhou Sopray SR05-170. Not much info on these. I did find a data sheet but it doesn't say efficiency of the panel.
I'd assume all these free solar systems use cheap Chinese panels that are not very efficient.

The panels Nuenergy list as using are SST 170-72M the catalog has them rated at 15.89% efficiency.



I am not sure if this is a fair comparasion panel for panel but this BP solar 170 watt panel is less efficient at 13.5%

[mate]

I t appears that any of these companies that are advertising their rings off are using the lowest cost materials, making the most of the government rebate, and taking full advantage of the 'innocence' and lack of understanding of the system by the bottom end consumer.
Yes it is a new market, open to the masses with these incentives and lower costs, but i believe it would be foolish to rush into a system that may cost more in the long run, when it needs to be upgraded to a set up that performs at full potential.

[dogsbreath]

Here is another one to consider.

On the dollar side of things
Sanyo hybrid panel 1kw system installed with sunnyboy 1100 $5000+
Nuenergy 1kw system installed sunnyboy 1100 < $1000
It is hard not to be a bottom dweller when looking at the price difference.

[SystemRat]

So if I go for the $5000.00 1 KW system how long will it be before it pays for itself. ??