Solar Power for home

[tagMan]

As the title suggests - thinking about putting in a 3kw system.
Who has a solar system - how big - before and after electricity bill - is it worth doing?
Any advice is great.

Thanks Brett

 

[stu99]

I have a 1.5kW on the roof since Feb, best daily output was 10kW.

Returns $330 last quarter through Energy Aust NSW, should do better with the longer days in summer.

Cost of the installation was $2500 after recs.

Keep in mind that most energy providers will try to put you on time of use metering if you are not already on it, and if you dont manage your power useage you will pay more on time of use metering.

However we reduced our quarterly bill from $800 to $450, with TOU and learning to be mindful of the energy in under 12 months.

It is nice to have $130 power bills now

 

[hutchstr]

i just installed a 1.5kw system..
hasnt been in long enough to get the new bill but we have generated about 200kw, so about $80 worth over what we have used ourselves, not that we use much power at all with only 2 of us...
3kw would be enough to just about have your house run totally from the solar power every year...

 

[WIR35]

Tagman,

In QLD, the metering arrangement (I believe) is gross metering. in this setup, your electricity bill is offset by the amount of energy generated by your PV array. This is not as good as some other states who use "net" metering, in which you pay for the energy used at your normal tariff, and then you are paid for the energy you generate at the current solar tariff, which is higher than the normal tariff. This means that if you were in one of the states which use net metering, you would be earning an extra few cents or so more than QLD for each kWh you feed back into the grid.

To be honest, have a think about how long you plan to live in that house, and then do some maths to find out how much it will cost, how much it will earn for you, and whether the system will pay for itself over the period of time you plan to be in the house. Also keep in mind that the PV system will probably add value to your property, so theoretically it will probably pay for itself much quicker than simply offsetting your energy bill, the system might cost you $10,000, but it might add $5,000 value to your property.

Also take into account your stance on climate change and your personal responsibility to the environment. That aspect is something which is difficult to put a dollar value on and is something quite personal.

I think you're going down the right track with the bigger 3kW system, if you're going to invest in a PV system, you might as well make it worthwhile.

 

[Biscuits]

Another thing to consider is the percentage and frequency of power price increases. Lately they have been climbing and fast, especially Qld.

I will be building in the next 12 months and i will be installing at least a 3kW system. Hoping to throw a wind turbine up too and never pay for power again.

 

[Beergutz]

Ive been told Aust government is going to pull the rug out from under everyones feet soon when it comes to solar power. They are going to reduce tariffs down to around 21c and are going to remove incentives for the purchasers....be careful

 

[hutchstr]

Ive been told Aust government is going to pull the rug out from under everyones feet soon when it comes to solar power. They are going to reduce tariffs down to around 21c and are going to remove incentives for the purchasers....be careful

i heard the exact opposite, I work for a builder and we have a close relationship with a solar company we use for our houses and they have been telling us different.. not sure if that varies state by state though?

 

[the_bluester]

WIR35, it is the other way around. The gross feed in tariff means you get paid for whatever you generate and you pay for whatever you use. A net feed in tariff means you pay for or get paid for the difference between what you generate and what you consume.

Beergutz, not sure that that is quite an accurate way to put it, but the gist of it is right. I have been looking into it (Two thirds as much power consumed this winter quarter in Vic than last year and a bill that increased by $100) the premium feed in tariff is about 60c/kwh (In vic anyway) and that scheme requires you to go onto TOU (Time of use) tariffs (Again, in vic anyway) which could without looking at what power you actually produce, easily increase your bill by 50% or more all by itself. There is a sunset date on that scheme after which no new applications will be accepted and there is also a generation requirement (I can not recall what it is) and after that many MWH of generation has been hooked up on the premium feed in rate, it also ends and no new applications will be accepted.

The 21C or so rate is the normal feed in tariff which you are still apparently supposed to be able to get, and it does not come tied to a TOU tariff. The gains are smaller but also so are the potential downsides, the peak rate on TOU is basically afternoon to evening (You know, the time you get home and do non essential things like cook food on your seriously power hungry electric stove!) and the peak rate is nearly twice the current normal rate, the shoulder rate in the later evening til early hours is about what the normal single rate is now and the off peak rate is cheaper. To me it looks like a pretty good deal for the power folks to get you on TOU. Not sure about for solar installs but I believe in Vic they have suspended allowing people onto the TOU tariff as welfare groups were up in arms about what it could cost some groups people who tend to be home all day and so would get hit harder by TOU others.

I am still thinking but I am a way from convinced yet. Another downside that they do not talk about. The subsidy is basically from someone buying your REC's on install. Basically that lets a high polluter offset your clean generation against more dirty generation to avoid penalties. The more RECS they buy, the more coal they can burn!

 

[tagMan]

Thanks for the reply's lads,

There is no time of use tariff in QLD yet. Up here they pay 44c/kwh generated and this is legislated till 2028. AGL pay an additional 8c/kwh making a feed back rate of 52c/kwh.

What we generate off sets what we pay on the bill. The solar company modeling shows they can reduce my bill by 90% with a 3kw system. ($10k out of pocket)

That would give a payback at today's rate in about 5 years. As we know electricity is not getting cheaper and even with inflated "salesman" benefit figures - i think i would easy get my money back in 7 years.

I think we will be in this house for another 10 years minimum.

Sounds pretty good.

 

[Biscuits]

Have you had a look at power storage?

Before everyone jumps on me. I am a qualified technician and am aware battery technology is shit, i'm not talking about storage of all power, just low use and emergency lighting stuff. If you convert you homes lighting to 12v (easy to do, especially with LED. You would never have to pay to switch a light on again. Plus when the grid goes down you can still play hungry hungry hippos with the family

 

[Dave]

This is not really a rant so its been moved.

Dave.

 

[Leprechaun]

Have you had a look at power storage?

battery technology is shit.

Check out the Ultra battery by CSIRO. UltraBattery: no ordinary battery (Profile - Project).

 

[the_bluester]

Have you had a look at power storage?

Before everyone jumps on me. I am a qualified technician and am aware battery technology is shit, i'm not talking about storage of all power, just low use and emergency lighting stuff. If you convert you homes lighting to 12v (easy to do, especially with LED. You would never have to pay to switch a light on again. Plus when the grid goes down you can still play hungry hungry hippos with the family

I have been looking into LED downlights. I reckon in another year or so they might have moved from early adopter territory to more commercially viable. A mate of mine renovated his kitchen and re did the lighting with 3 X 1W CREE diode downlights. It needed about twice as many of them to get a good and even spread of light but the whole lot still comes up at about 60W total.

Some seem to be a better design than others. The CREE 12V AC ones run on 12VAC or 6-24VDC where some are straight plug in 240VAC jobs and I wonder how they are dropping the voltage, via an internal reg (Which I suspect as they run a hell of a lot hotter than the 12V jobs) or with a small step down transformer in each light. The lower voltage ones look the goods to me and the benefit would be that with a bit of well thought out circuitry you could use them in a poorly lit (By daylight) area hooked to mains at night and a solar panel by day so you get light all day long. I reckon they need to come down by about another $10 per unit before I will start making the move myself. And every day I wait is another day closer to someone producing a LED that equals a low voltage 50W halogen in one lamp assembly which would be a real clincher for people to start moving over. If I built a new house it would have LED lighting from the start.


I have wondered with storage systems how long it is going to take some cheeky (Smart) bugger to come up with a grid connected solar setup on TOU with storage batteries and some smart charge controller software so you run off solar during the day until the light runs out, most likely contributing back to the grid for a good part of the day, have the batteries to float you over the end of the peak tariff, run off the mains input in the shoulder tariff in the evening and then charge the batteries on the cheapest off peak tariff at night. That would have you sell power back into the grid all day (If you are not home) avoid drawing off the grid for most or all of the peak rate time by drawing down the batteries and then recharge them, buying power off the grid at the cheapest rate available, ready to start selling back almost as soon as the sun comes up.

 

[Biscuits]

You could always go the remote set up and piss the grid off all together. Only ever drawing power off grid if you have a battery failure.

 

[hutchstr]

I have just put about 30 LED downlights in my place, they are 5w each so i can run 10 of them off 1 transformer.
they dont run hot at all. mine just have the 1 LED per light with a dome bit which gives the angle on the light. You dont need anymore than what you would normally install with the 50w globes, they are pretty bright. they are definately a different sort of light though, even with the warm white ones they look a bit different, but i think it looks better
apparantley the globes have a 50,000 hr life span, so it doesnt work out much more expensive considering how many 50w i normally change over the years..

 

[the_bluester]

It would be interesting to have a log of power consumption to see what sort of inverter capacity would be needed to support a modern house (I am a bit of a tech head so we are not the most frugal people on earth)

We have been hovering around the edges of a solar debate at home for a couple of months, but I find the frenzied sales pitches from the installation mobs extremely off putting, makes you wonder what they are glossing over. One mob were spamming my mothers fax with different ads to the tune of three to four different ads from the same crowd each day. It got so bad we ditched her fax to save on the costs of keeping paper and ink up to it. Puts me in mind of snake oil "Miracle" cures.

 

[WIR35]

bluester, I have 6w warm white MR16 lamps in all of my downlights in my place. Their light output is roughly similar to about a 35 watt halogen, both in intensity and colour. They are perfect for rooms where you don't need a bright light such as lounge rooms, hallways, toilets, bedrooms, patios and in garden lighting etc. I would not use them in a kitchen, bathroom or laundry. They run off 12 volts AC, and work best from iron core transformers.

in saying that, most of the well known commercial lighting brands such as pierlite, zumtobel, JSB, etc have used LED technology and have come up with very good commercial quality fittings. It has been a very rapid evolution which has seen LED downlights new being par for the course in commercial fitouts in offices, hospitals, universities etc (the only people who can afford it...) They are very expensive to buy, but more importantly is the cost of ownership, which takes into account energy usage and lamp replacement. In terms of cost of ownership, the LED technology kicks arse over incandescent or even compact fluorescent luminaires. In residential applications, cost of ownership is not a big of an issue because lights are only on for a couple of hours a day, not on for 16-24 hours like in a commercial situation.

Pierlite have recently launched a 12 watt warm white LED downlight kit, which looks exactly like your everyday halogen downlight kit and the light output is comparable or better. They come complete with fitting, lamp, power supply and flex and plug. They cost around $85 trade, or about $110 or so retail. Very impressive fittings and are now widely used (we are putting in approx 600 of these in a job we are doing).

 

[the_bluester]

Have you got a manufacturer and part number for the 6W downlights? And what was the unit cost of those ones?

A lot of discussion seems to be out there abotu what the actual power consumption of these things are. One I know of is advertised as a 9W lamp (Three LEDs) when in fact the power consumption is closer to 4W with light output to match. They were advertised on the common max power rating of the LED in use, which is known as a three wat LED, but in actual fact is about 2.5W at it's max drive current and then the lamp manufacturer drives them for about 1.3W for longevity.

Much smoke and mirrors out there yet in the domestic market is seems. But we are in line to refresh the lighting in our place (The house is 35 years old or so and the lighting design seems to have been "put one here, and here, and maybe here", not a lot of thought went into it) I have just started looking seriously at options to do it. I do wonder how they arrive at a 30 to 50 thousand hour life of the lamps though, unless they developed these LED's nearly six years ago and have had them test running 24 hours a day ever since they would be years away from the expected replacement point at 50,000 hours. I hope it is not like some radio equipment I saw installed while I was in the RAAF. the MTBF (Mean Time Between Failures) was supposed to be in the decades, the first one was dead in the box and the second let the smoke out after two days!

 

[Jason]

And in today's news............

Popularity sees solar rebate scheme slashed - ABC News (Australian Broadcasting Corporation)

The New South Wales Government is slashing the tariff it pays under its solar bonus scheme.

The scheme was introduced in January and pays 60 cents per kilowatt hour for all energy produced. It is meant to run for seven years.

The Premier says more than 50,000 households have taken advantage of the scheme and are generating nearly 200 megawatts of power.

Kristina Keneally says the cost of solar panels has halved and that has led to a greater than expected take up, which is putting pressure on electricity prices.

To make the scheme more sustainable, the tariff for new applicants will be just 20 cents per kilowatt hour from midnight tonight.

Ms Keneally says that will slash $2.5 billion out of the cost of electricity prices.

"This is about reducing the burden of electricity prices on the household budget," she said.

 

[WIR35]

Bluester, I got my LED lamps from Prime Electronics http://ns.prime-electronics.com.au/index.php/lamps-and-modules/lamps.html . See photos attached. The actual fittings are called a Telbix "cube" and cost around $7 per frame (retail price about $15-20). The transformers I am using are the tried and tested ATCO iron core black 12V 50watt. You can run up to 7-8 of these LED lamps from one transformer. The fittings I used are great for these lamps, because the lamps are set back 20-30mm into the fittings they are low glare and don't shine into your eyes. they are also fully dimmable using Clipsal universal dimmers.

Originally we were recommended not to use these lamps with electronic 12v transformers, but we have tried them and they seem to work fine, we've had a few running in our office for about 12 months without failure on electronic transformers. This means that if you have a house full of 12v halogen downlights, you can swap them for these LED lamps, with a relatively comparable light output. They emit virtually no heat, which means less cooling/air conditioning required in your home too.

I pay around $25-30 per lamp, but if you do your homework and look on ebay or overseas you could pick them up for probably less than half that price.

For those who are interested, there's no reason why you couldn't run a photovoltaic array fitted to a bank of 12V deep cycle batteries, and then run your lighting circuits as all 12 volts. This would mean you'd never have to pay for your lighting again, and if you have a power outage you still have light....