Thread: Solar power

Whoooo, what a lot of replies; it seems that I may have hit a nerve somewhere.

Sir Stinky

Thank you for your detailed and thoughtful post.
I am insisting on an SMA inverter. I realise that many other inverters may be just as good or possibly even better, but the majority of people who have owned one of these say it is the best one around, so be it. I could go with a smaller SMA inverter but I would much rather over-engineer than under.

I was pleased to read your comment re the pricing, because that also went with my own uneducated thoughts on the subject, and that about $10K was probably a far more reasonable price for that system.

With the electricity price hikes announced today, it is likely that I could pay off the investment even faster than I originally thought possible.

I have just got off the phone to Positronics, They are a Brisbane solar installation firm, and I hope to get a quote from them in the next couple of days

Joe

Yes, they did explain that about the 1/2 and 1/2 power, but I will get a mid day period when I expect to get both sides working for about 2 hours.

Issatree

Where did you get $20K from. I expect it to be about half that, and as I said to Sir Stinky, the recent price hikes will see me better off sooner than ever.
yes, I am 68 years old, my mother is now 98 (still in her own home) and I expect to be older than her when I die.

Malibu (John)

If you have reduced your bill by that much then I hope to do even better.
If I leave $10K in the bank at 5% pa then in 7 years time I would have about $12,762. At current rates, I am not even making that, so it would definitely pay me to invest in solar and remove all my future bills if possible.

If you are saving $550 a quarter on your bill, then I would get a pay off the system in less than 5 years.

Wongo

Inspire -- kick in the nuts and run, got it.
It isn't hard to use 20kw a day when you live in a climate like Brisbane has. I have a large main A/C that use 8kw an hour when running full blast, and a much smaller one for use in the bedroom at night. Sydney's climate is obviously a bit easier to take. I read lots of stories about how ancient people (such as myself) suffer from heat stroke and die. I don't want to do that just yet, so I will continue to use the A/C.
I also have about 3 or 4 computers running, plus I have a workshop to run under the house. The stove and oven and hot water are all gas, so no electricity is used there. It is probably the extra large TV that uses all the other power up.

Malibu again.

You mention bluetooth connections. I don't have and Bluetooth items in the house, so how do you actually connect to it?

Robson Valley

I am definitely not a greenie . I don't care about carbon either, I just want to save money.
You tell us how you can get away with just 1Kw of solar, but what about your electricity bills? What do they amount to per quarter?

Malibu (yet again)

$1200 a quarter? I sympathise.

Stuart
If I live that long (see above), I will endeavour to report back.

You mention bluetooth connections. I don't have and Bluetooth items in the house, so how do you actually connect to it?

Errr... it's a little blue tooth dongle thingy that plugs into a USB port on the computer. I'm not even sure where I got it from - probably flea-bay - but (once it's set up, configured, etc etc..) I start up the Sunny Explorer software, which came from the SMA website, log onto the unit and access all the information it has in its brain.
The previous picture I put up of the Kwh graph is a mosaic of the yearly data from the unit.
It tells you the current kw's, any faults, previous readings by day, month and year, plus a whole lot more. It's good to look at and see how much sun, and at what time, was falling on the PV cells.
You could 'tap' the front panel on the SMA and it will scroll through the produced data........ but that's no fun

I have just had installed a 4kw system, SMW sunny boy 4000TL inverter and 23 panels (3.99kw)for about $7k.
Inspections to go before it is connected.

Originally Posted by Bob Willson

I could go with a smaller SMA inverter but I would much rather over-engineer than under.

Bob .... unfortunately it is not that easy. The inverter really should be sized to the number of panels you have. Having a much bigger inverter than you need will not necessarily produce better results and may be a negative for the system. It all has to do with start up voltages. If you put 1kw of panels on a 5kw inverter it may not actually wake up!

The SMA website has a really good program that allows you to play around with creating your system. You can select the site specific data (orientation and the like) and then an SMA inverter. There are heaps of different panels to select and when you have a few quotes you can compare the different expected outputs from the different panels that you will get recommended. You can quickly change the panel configuration and see what impact it will have on the system. The program also tests things such as low voltages and the like. Well worth having a play with as you will learn quite a bit and actually know more than the people who are quoting you.

Originally Posted by Malibu

Errr... it's a little blue tooth dongle thingy that plugs into a USB port on the computer.

Thank you John
I do actually know what bluetooth is and how it works. My question related to the actual making it work as it is my understanding that for Bluetooth to work you need to place the little USB stick thingy into close proximity with the Bluetooth enabled item.
My desktop computer is about 30 metres away from the where any potential Bluetooth enabled SMA inverter would be installed and as it not very portable (neither one of the items) how would I get it to work?

I do actually know what bluetooth is and how it works.

No offence meant by that Bob... I know very little about bluetooth, especially the one I have - so it's a blue tooth dongle thingy.

My question related to the actual making it work as it is my understanding that for Bluetooth to work you need to place the little USB stick thingy into close proximity with the Bluetooth enabled item.

I just plugged it in, did a search for blue tooth in range and it found the SMA itself. All I had to do was pair it up. It was a couple of years ago, but I'm sure it wasnt all that hard to do and this is the only bluetooth connection I've done here.

My desktop computer is about 30 metres away from the where any potential Bluetooth enabled SMA inverter would be installed and as it not very portable (neither one of the items) how would I get it to work?

My computer (in the office) and inverter (one floor down in the workshop) are I guess about 20-25 metres apart with a chipboard floor in between. Seems to work OK as it is, but does have the occasional comms failure with logging on.

Originally Posted by Malibu

I just did the maths on usage for the septic... $200 a year JUST to run the control panel without the motors ever coming on...

According to my maths thats near enough a 100W load..........just what is that panel doing!!!

Stuart

It's the light over the panel that helps him read it in the dark. Oh, I see it's a 100 watt bulb

Originally Posted by Malibu

I just plugged it in, did a search for blue tooth in range and it found the SMA itself. All I had to do was pair it up. It was a couple of years ago, but I'm sure it wasnt all that hard to do and this is the only bluetooth connection I've done here.

My computer (in the office) and inverter (one floor down in the workshop) are I guess about 20-25 metres apart with a chipboard floor in between. Seems to work OK as it is, but does have the occasional comms failure with logging on.

Well it sounds as though it will be very easy to do then. Thanks.

Originally Posted by Stustoys

According to my maths thats near enough a 100W load..........just what is that panel doing!!!

Give or take meter errors, I tonged it at .25A which by my maths is 60W, but I'll be first to admit, the meter doesn't handle the low currents well.
At that reading it's 60W, so it actually works out to $189.22 - Sorry for the confusion

Originally Posted by Malibu

Give or take meter errors, I tonged it at .25A which by my maths is 60W, but I'll be first to admit, the meter doesn't handle the low currents well.
At that reading it's 60W, so it actually works out to $189.22 - Sorry for the confusion

I also have one of those septic systems with a recirculating and a pump out pump, they do consume a fair bit of power.

After I cut back on both the number of recirculating cycles and their duration, with no ill effect on the septic contents and colour/odour of the final pumped out grey water, our electricity bill reduced markedly. I also put most of the run time in our off-peak billing time (11pm-7am)

No light on the panel though, just a LED and an LCD readout.

Just a few comments on solar,we put a 20 Kw system in on nov. 2011, 20 panels 4.4 Kw inverter at about $11k
We got in on the good feed in rate of 60 c + 6c from the retailer,so far to date have banked over $2400.
If you add the cost we would have paid for power,about $1300 that makes it $3700 in 15 months so pay back in around 4 years.

Originally Posted by nrb

We got in on the good feed in rate of 60 c + 6c from the retailer,so far to date have banked over $2400.
If you add the cost we would have paid for power,about $1300 that makes it $3700 in 15 months so pay back in around 4 years.

Lucky Bugga. That ain't gunna happen any more.

I get an electricity bill every 2 months so I'll prorate it for 3 (a quarter).
My demand is highest right now in winter. The days are very short at the solstice.
Theoretical sunrise and sunset times are meaningless due to the mountain ranges within a couple of km of the house. Dec 21, I watched the sun disappear at 2:10PM. So, more lights on for longer.
My Harman P38+ compressed wood pellet stove has 3 electric motors for a sum of approx 500W and the stove runs 24/7 from October to April (except for shutdown cleanouts every 1,000lbs or less, depending on pellet quality.) For heating, it saves me about $1,500/year when compared with the oil furnace.
My use of electric bar room heaters is quite arbitrary. Two winters paid off the stove, 2 more winters and all the solar was recovered, too.

At any time of the day or night, we can have power failures which last from a few seconds to 8+ hours. NOT FUNNY at -20C with a wind. So, my little solar system will run the stove for about 10 hours.

It's midwinter now. My last electricity bill was $165 for 3 months. In that time, I've burned 2.5 tons of pellets = approx $540, to keep the upstairs kitchen at 18C - 20C.