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Russ

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There is a lot to do on the inverter side that most people don't have to consider but being in the radio business it is a huge issue for us. Most inverters are filthy dirty things when it comes to EMI and can disrupt a lot of electronic equipment. I am doing work for a mate of mine that makes a salt water pool chlorinator that is now starting to takeoff in the USA market. We had a unit locally that was going berko so I went out there to have a look and found the customers 5kw inverter was emitting so much noise onto the electrical system it was sending the mains timing pulse stupid we use for the micro in the unit. turn the inverter off and it works perfect also if you have any low frequency radio say under 10 mhz it is almost useless…they didn't know because they listen to VHF FM radio not any AM radio. I know the first 5 kw inverter I had here I could not listen to 4BH it wiped if off the map but this new one (Growat) is much cleaner…still emits some crap but no where near as much as the original Sunnyroo

 

So a panel that has its own inverter in it I would have to see how good it was but it would only have small capacity it would be a specific use item for say one small appliance. trying to get a heap of these tip panels together would create some headache synchronising them all together as a AC unit

 

 

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I used Total Solar for my house at Burpengary and also up at my farm. As solar companies go they were ok to deal with and did a good job with their installers these are grid connect systems and were a good price when I got them put in. I am looking seriously though at going off grid in the future and just using solar with batteries the same as Dutchroll above. Qld govt are changing the "fixed" rules so the 300 I save at my house per quarter will go with the access fee they will charge and the 600 plus cheque I get from Ergon each year from the farm will only be 300 after the access fee....both sites are on the 44 cent rebate. I use solar at our radio sites and the biggest problem is getting reliable batteries they all quote big years out of them but in reality they rarely make it and are expensive.I am looking out for the old style batteries we used to power all the electricity substations with when I worked for SEQEB another lifetime ago (Energex now). They were bullet proof and lasted 20 to 30 years they were huge wet cells 2volts each in square glass containers with V plates at the top they were lead acid and just never failed.....they required maintenance but were truly fantastic. The other advise is work out your total load of the house and anything else you can think of and make sure your inverters are at least 30% bigger than the most load you can hit them with. Overhead in the inverter is important I have seen a lot die. The ones at the radio sites we now use 50% bigger than the load required and do not have any failures any more

what about NiFe cells? they last forever: there was some electric car made with NiFe cells in about 1900 and a few yrs ago I read they still worked. There's a place in China makes them.

 

 

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Apparently the navy changes them after xx years and they end up with second hand dealers.

 

You would imagine they would be the ducks guts.

 

Very low voltage I think, so afew would need to be joined up.

 

 

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actually you cant add to it if you only got a 1.2kw inverter that is what your contract is for if you install a bigger unit they will make you sign a new contract for 8 cents not 44 or 55 depending on who you were with.

 

I just upgraded my system, no change to contract and the inverter could handle it. Nice to not have to pay electricity bills, but if i sell, the new owner will not have the same contract, so it will be worth less to me at sale time.

 

 

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The older submarine were NiFe (Nickel Iron) batteries and are alledgedly damn near immune to over/under charge problems you can run into with standard Lead Acid or the newer Lithium batteries. The downside is they are a lower voltage (1.2V i think) compared to a standard lead acid cell (2V), which means you need more of them. They also have a different discharge curve, and modern inverters will often cut off (to protect the batteries) too early for a NiFe battery.

 

Anyway, back to the topic. The solar stuff is like anything really. Do some research yourself so you've got something to judge the amount of bullshit your getting fed by the sales droids. Have a good idea what your daily usage is like, roughly how many peak sun hours you get in your location (check BOM site for data), roughly what size you want. the size and the peak sun will give you a rough average for how many kWh a given sized system will produce every day (probably better in summer, worse in winter obviously). Check brands of panels and inverters - some are better than others.

 

 

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...The solar stuff is like anything really. Do some research yourself so you've got something to judge the amount of ******** your getting fed by the sales droids. Have a good idea what your daily usage is like, roughly how many peak sun hours you get in your location (check BOM site for data), roughly what size you want. the size and the peak sun will give you a rough average for how many kWh a given sized system will produce every day (probably better in summer, worse in winter obviously). Check brands of panels and inverters - some are better than others.

Good advice, sain. I bought the smallest system (1.5kW) in the belief it would cover my largest single user of power- a water pump. The rating is probably based on absolutely ideal conditions. The most mine produces is 1200 watts at midday on a clear midsummer day. I should have bought a 3 or 5 kW system to cover the rest of the time.

As a grid-connect system we are paid very little for the power we export, so most of our heavy use is during the middle of the day, so that we are using our own power first. Pretty easy to do with timers.

 

 

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Guest Andys@coffs

I worked out for my family of 4 (2 teenage daughters) that we used on average 22kwh per day (which is a lot!!) I put 6.5kw of Sanyo TF panels on the roof (expensive panels, but lowest reduction in output as heat increases available at the time, 32 x 210W ea) int0 a 6kW SMA inverter (with transformer) In NSW I generally get a cheque from the retailer of between $800 and $1200 per quarter. But I "invested" about $32k after STC's in the solution quite a few years back now.

 

I found that if I cleaned the panels with soapy water (and yes the broom did have a dry wooden handle!!!) each quarter I could significantly affect the output for the quarter. During that time a new 4lane highway was/is being built so dust builds up quickly.

 

As suggested above in NSW we have a gross system where the meter measures separately what is produced, and what is consumed. when the current 65c per kwh system disappears I will change over to a net system as fast as I possibly can. At that stage I presume I will start to pay them again, but I think from memory the system goes out to around 2016...... Originally I worked out that by the end of the scheme my system will be fully paid for and that everything it produces for the remainder of the 25 to 50+years I expect from quality #1 panels will be a bonus. I accept that getting an inverter to last that long may be a tough ask, but the panels should easily do it! I'm told that the first solar panels ever produced are still producing at around 70 - 80% efficiency of their day 1 outputs......

 

The real trick is making sure that if you have different groupings of panels, some facing a different direction etc, that your inverter has separate maximum power transfer tracking inputs. Cheap inverters only have one input, better inverters have 2 to 4. When the panels are all wired up to the 1 input any shading due direction or TV antenna or trees etc on a single panel (and it only needs to be a part shading of the panel not even the whole thing) will take the whole output down to close to zero. Where you split into logical groups the same shading will only take out the group not the entire system. On the otherhand the higher the voltage the less impacts are seen by cable resistances. as you split into groups you raise the losses due to cable resistance, so its a balancing act, all the while ensuring that the input voltage doesn't rise above the maximum that the inverter can handle (and that needs to be no load high, cause it will drop when the inverter switches from monitor to produce)

 

Andy

 

 

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Update....heard today that fed govt is about to re cost the about to expire rebates, ie 8 cents per kW.

 

Mooted to now be around 14 cents per kW. Those that got onboard at 44 cents, are going to be re costed, to ??......a lot less.

 

Those that went way over the top producing massive amounts of energy are in the firing line for the razor gang.

 

How this all pans out, will be interesting.

 

 

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Update....heard today that fed govt is about to re cost the about to expire rebates, ie 8 cents per kW.Mooted to now be around 14 cents per kW. Those that got onboard at 44 cents, are going to be re costed, to ??......a lot less.

Those that went way over the top producing massive amounts of energy are in the firing line for the razor gang.

 

How this all pans out, will be interesting.

For those residents already on the 0.44 rebate program, what is the proposed ammended rebate now going to be ?

 

 

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At that stage I presume I will start to pay them again, but I think from memory the system goes out to around 2016...... Originally I worked out that by the end of the scheme my system will be fully paid for and that everything it produces for the remainder of the 25 to 50+years I expect from quality #1 panels will be a bonus.

I heard on ABC radio that the seven years will be up at the end off this June. I got approved for the $8000 grant but got cold feet and didn't proceed, turning over to smart metering with mostly night electricity use didn't make any sense at the time.

 

There was a CSIRO researcher speaking on the radio about storage technology improvements, she suggested the leaps and bounds for battery technology are still two years away from commercial release, can't remember now what technology that was.

 

 

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Update....heard today that fed govt is about to re cost the about to expire rebates, ie 8 cents per kW.Mooted to now be around 14 cents per kW. Those that got onboard at 44 cents, are going to be re costed, to ??......a lot less.

Those that went way over the top producing massive amounts of energy are in the firing line for the razor gang.

 

How this all pans out, will be interesting.

I have trouble understanding how they can pay people less for the power they put back into the grid than the person pays for what they take off the grid. I can understand WHY they do it, because they're a bunch of ****s and they don't want renewables to succeed.

 

 

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I have trouble understanding how they can pay people less for the power they put back into the grid than the person pays for what they take off the grid. I can understand WHY they do it, because they're a bunch of ****s and they don't want renewables to succeed.

Power companies losing too much money and whinging to the government.....

 

 

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I have trouble understanding how they can pay people less for the power they put back into the grid than the person pays for what they take off the grid. I can understand WHY they do it, because they're a bunch of ****s and they don't want renewables to succeed.

Right on Marty. I've been told several stories by power company people. That my surplus power only heats up the nearest transformer and never gets onto the network. That they pay us the same rate as they pay for coal-fuelled electricity.

 

Better-qualified advice has our little roof-top panels making quite an impact miles from source, so the power companies are getting current locally on the cheap. Perhaps the main problem is that their system was never set up to cater for intermittent solar feed in.

 

Perhaps things will play out like they have with Telstra, who still must maintain the cable network while consumers are shopping around and using various wireless services. As more of us generate more of our own electricity, cable-access fees will increase.

 

 

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The solar reduces peak power needs which are (or were) on HOT days when all the air conditioners are on. Some coal fired power is as low as 3 cents perKw/h at the power station. The rest is infrastructure (about 15 cents) and advertising /profit for the name on the top of your bill.(usually about 8 cents) It's worth paying an amount to have the power available at your premises. (usually about $300) . When you turn a switch on you get power when YOU need it but one small change is nothing like a heap of buildings running aircond. The advent of solar has probably reduced the need for 2 power stations. Nev

 

 

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... The advent of solar has probably reduced the need for 2 power stations. Nev

I remember when the likes of John Howard dismissed the potential of renewable energy. A few short years later (with a little kick start from government) we are starting to wean ourselves off fossil fuel. Along way to go yet.

 

 

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I have 20 panels and the biggest inverter , i installed it myself (with the help of sparky) in 2 years it has paid for itself and i have $1100 in credit , solar works well for me ,we are on the top tariff of 52 cents , we also have a air-con integrated system so it is a definite winner for me

 

cheers Gareth

 

 

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Kyles comment about solar being dirty wireless wise. ie not a clean sine wave got me thinking. My radio has got very noisy lately, probably since I had the solar upgraded.

 

I turned the solar inverter off and instantly all the noise in the radio stopped, turned on again and it came back as the inverter fired up.

 

Will have to see what i can do to get clean power to the radio and maybe it is upsetting the computer as i can't send large files over the internet.

 

 

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There is a lot to do on the inverter side that most people don't have to consider but being in the radio business it is a huge issue for us. Most inverters are filthy dirty things when it comes to EMI and can disrupt a lot of electronic equipment. I am doing work for a mate of mine that makes a salt water pool chlorinator that is now starting to takeoff in the USA market. We had a unit locally that was going berko so I went out there to have a look and found the customers 5kw inverter was emitting so much noise onto the electrical system it was sending the mains timing pulse stupid we use for the micro in the unit. turn the inverter off and it works perfect also if you have any low frequency radio say under 10 mhz it is almost useless…they didn't know because they listen to VHF FM radio not any AM radio. I know the first 5 kw inverter I had here I could not listen to 4BH it wiped if off the map but this new one (Growat) is much cleaner…still emits some crap but no where near as much as the original SunnyrooSo a panel that has its own inverter in it I would have to see how good it was but it would only have small capacity it would be a specific use item for say one small appliance. trying to get a heap of these tip panels together would create some headache synchronising them all together as a AC unit

G'day Mark, Julie and I are looking at putting in a system here on the farm (5kw). What inverter/s should we stay away from knowing that I operate HF radios BELOW 10Mhz? Prob something to discuss with you next time you are here.

 

Cheers

 

 

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