Power generation system. Part 2

After some investigation, I've decided to CONSIDER a completely different approach to a petrol, or diesel generator. I can buy a 3kVA inverter for about $3k and some Solar cells (10 X 115Watt panels) for another $8k. The gummint gives me back $4k (yay!). I have plenty of easily accessible (

Reply to
Trevor Wilson
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Only if your inverter is the appropriate type. Not sure if the price you mention for 3kVA is for a stand-alone or mains-connectable. The batteries sound cheap. Mine are 700AH, 24V and cost $4000 new. The rebate also has conditions - e.g. the system must use NEW components (I think) and be installed by an accredited installer etc. Alan

Reply to
Alan Peake

There is no replacement for a generator. Every decent set-up still needs one...

Fair price...but for the system to operate without recharge from mains or diesel generator, you would need a lots of modules. Do not forget, 115 watts is peak power. You can count on 1/2 average per day. 5 modules (24V) would average 600W. You would need much much more than that.

It is if you meet conditions. There are plenty....

The most important part of the system is, guess what, the battery bank! While everything else can be second hand and still work, there is no such a thing as "refurbished second hand" stationary battery that still have enough capacity for the system.

few extra

The proper term would be double Whammy. Kilowatt produced by the system would cost at least 3 times more than from the mains. If approved, power authority will pay you fraction for what they charge.......

No neighbour problems and get to have a warm, fuzzy, green

The hybrid power generation is hijacked by the global oil corporations. Basically, there are no real investments or R&D. They are waiting for oil to run out or when pollution is prohibitive to use oil. Therefore, cost of the components is just too high. We can only dream to see solar panels on every roof in Australia. There are thousands of panels along German highways, but not many here....

Do the maths better....

Reply to
hadda hadda

**$4.5k for the mains-connectable type.
**Batteries are second hand.

The

**I figure on leaving the batteries out of the system, then installing them later, just unsing mains interactive inverter. The acredited installer part should not be a problem (I hope).
--
Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

**Bugger.

**Yeah, sorry 'bout that. $4.5k for mains interactive.
**I plan on using 10 modules. Maybe adding a wind generator (200W), if I can slide it past the council and neighbour objections.
**So I've found.

**My battery guy has a fair bit of experience in this area.
**Typical.

**I'm pretty certain I already have.
--
Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

only

What about hydrogen fuel cells?

Last forever, no batteries required.

The way of the future.

Reply to
Sam

**What about consumables?

**Perhaps. However, I am searching for a practical, reasonably priced, doable (right now) technology.
--
Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

Silicon manufacture for solar cells requires more energy than the cells can make in thirty years, that doesn't count the energy to process the silicon into solar cells or the losses to store the energy made by them.

If you look closely at the manufacturer's specs you'll see the power drops off to about 80% after ten years, due to micro fractures in the silicon material causing performance degradation and a life of about 20 years.

You'll most likely be doing the environment a favour by buying an alternator instead and just using it when neccessary. With proper maintenance and storage it probably will last longer than the cells anyway and definitely longer than the batteries you'll need.

The added advantage would be that it's compact, cheaper, higher in output and needs less space than a solar installation would.

Regards Mark Harriss

Reply to
Mark Harriss

Just wondering mate, what brand of inverter are you thining of going for?

different

for

The

( >> Metres from ground level), flat, unshaded roof space for the panels. I

green

Reply to
Joe

"Trevor Wilson"

** You need to broaden you horizons - Trevor.

If your power goes off - then so does the whole area.

There is an *opportunity* here.

Get a 20 kVA diesel gene and some long extensions, so you can supply power to your immediate neighbours.

10 neighbours at say $50 a day could be quite lucrative.

Charge that pesky Leb next door double too.

......... Phil

Reply to
Phil Allison

G'day,

Solar really only adds up economically when you're in the middle of nowhere and have to generate your own power. Mains power is actually really good value when compared to trying to generate it yourself. Power 24/7 aint cheap to do.

If you want backup, have a look at second hand places, machine yards, auctions etc. A quality second hand genset is better than a $100 pile of shit from bunnings. I got a 3kVA online UPS at an auction not long ago for $20, batteries were stuffed but after getting some new batteries I had a 3kVA online unit for the same price as a 400VA standby unit. Actually if you get an Active online type UPS you could pretty much use any generator you liked as they rectify all the incoming mains and invert it again.

Good Luck

Reply to
j.l

Seriously, My house would run comfortably on < 1 kw/hr (not counting washing machine)

I have compact fluros everywere, with only 2 - 3 on at one time, The TV when used and computer,

Cooking / washing is done by natural gas. My last power bill was a miniscule $70 for the last 90 days that, i belive is bloddy good.

we have 1 fridge and 1 chest freezer that run when needed. I dont use heaters much if at all, the heat generated during cooking is enough to provide the evenings heat.

if i were to switch most items to 12V (lights etc) i could run alternative energy sources. why 12(24) up convert to 240 for lighting when you can jsut use cheap and power friendly CCFL's? LCD monitors run internaly from 12v (most anyway) and as long as your not running a P4 your computer can run low powered too. s**te, the acer 995 sempron laptop would work well in an alternate power environment.

Houses don't need to use much power,just people are mindless about leaving things on when not needed.

Reply to
Matt2 - Amstereo

"Matt2 - Amstereo"

** Huh ?

You have a gas powered washer ??

You do not own an electric jug ??

I bet your hot water is gas though.

Plus I bet you live where the climate is warm.

** Many residences have no gas appliances or supply.

A small electric water heater takes 3.6 kW.

A basic electric stove takes 5 kW when the oven and 4 tops are all on.

A small room heater takes 2kW and an electric jug the same.

On a cold evening, while cooking dinner - the whole lot may be on.

That is over 10 kW not counting lights, TV or fridge.

......... Phil

Reply to
Phil Allison

no,. refering to hot water you know dishes, shower etc

Yeah but im refering to being able to run most / all heating without electricity meaning that alternative power is viable

As i said above we have natural gas

No, ipswich is always colder than brisbane in winter, however jumpers or jackets are great money savers

easy to have fitted or installed (a must for alternative electricity) and the savings are pretty good to.

no good for alternative electricity

no good for alternative electricity

no good for alternative electricity

Gas is a clean viable and cheap alternative for all these. (and yes you can get gas fridges, though the costs may or may not be different

Any thing that envolves heating can be run on gas. I perfer to cook on gas simply because of control and instance.

The orig poster was on about alternative energy, i don't think hed go to all the trouble of fitting a collector / bank just so he can use it for burn an element. Resistive heat is the most draining on any power system, using a burning flame is by far the most efficient way of heating somthing. Gas matey, Gas.

Reply to
Matt2 - Amstereo

**Sprouting an old myth does not make it true. I suggest you do some actual research before you make a comment. FYI: The actual figures for payback (energy required for manufacture) is more like 4-5 years.
**Depends on the cells.

**And it will create noise and pollution in the process. Solar cells are silent and do not produce pollution.
**And far less convenient, noisy, polluting, requiring maintenance, fuel, etc. All in all, a complete PITA. It would also defeat the secondary purpose of the whole system. It would, however, satisfy the primary purpose.
--
Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

**I have yet to determine that. If anyone has a suggestion, I would be all ears. Here is my source:

formatting link

--
Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

**Something I had considered, if I went diesel.

**Not a chance. Not for any amount of money.
--
Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

: : The orig poster was on about alternative energy, i don't think hed go to : all the trouble of fitting a collector / bank just so he can use it for : burn an element. Resistive heat is the most draining on any power : system, using a burning flame is by far the most efficient way of : heating somthing. Gas matey, Gas.

I do share your sentiments on gas.

What a novel idea would be is to harness the great, untapped methane resource that resides in Phil. He is just so full of the "brown smelly stuff" you could power a small city on it ;-)

After reading that "Strobe" thread I very much doubt anyone would disagree.

Regards TT

Reply to
TT

**I just performed a more detailed analysis. Urk. I will require 20 X 115 Watt panels, not 10. That is, of course, assuming I don't make any conservation moves. At present, I get by on around 13kWhr/day. Adding Solar hot water should drop that figure by around 5kWhr/day. Give or take.

This will require more thought.

--
Trevor Wilson
www.rageaudio.com.au
Reply to
Trevor Wilson

Here are the figures I'd researched a month or so ago for another discussion. Solar cell makers buy surplus semiconductor grade silicon for manufacture of their cells, so they should count the energy cost to refine silicon to this stage. There are processes to make "Solar grade" silicon out there but none are past the lab stage of testing: these take 1/3 of the energy to make the silicon. At any rate here is the figures I've come up with.

The calcs assume:

  1. You are living on the sunniest place on the planet with 3000Hrs of sun per year, somewhere on the equator on a cloud free plateau, Sydney/Melb figures will be greatly reduced as you are closer to the south pole at sea level in air pollution.

  1. The solar flux is a constant unvarying 1.4Kw per square metre from the sunup to sundown.

  2. There is no age related loss of power at all(more like average 10% and peaking at 20%).

  1. You have invented some new way to slice silicon that has no losses. The figure is closer to 50% at the thickness I have quoted.

  2. The only energy costs are that to make the silicon, nothing else. Please not that this does not count the lack of efficiency of energy storage in batteries, the cost of making the batteries, the cost of making the inverter, the cost of converting the silicon into a cell the cost of refining the metals and glass used in the solar system or the cost of shipping and installation.

6.It also does not count the multiple sets of batteries over the life of the system.

  1. It does not count the CO2 made during the chemical combustion part of refining the silicon with carbon from quartz.

Here's what I'd researched earlier, Trevor on the 19/05/05:

"I've read it's a six step refining process that requires 2130 KW/h per kilo of silicon. The density is 2330 kg/cubic metre, so assume you can slice the silicon to 0.5mm thickness and have no sawing / polishing waste and no energy expended to saw / dope / connect the cells,you'd get

2000 square metres of silicon for just under 5 GW/hours of energy. Solar radiation is ideally 1.395 KW/metre square by 2000 square metres cell area @ 3000 hours per year of sun under ideal conditions at the best spot on the planet.

This gives 8.370 GW/hrs of energy per year by 15% cell efficiency to give 1.255 GW/hrs per year of electricity.

so 5 GW/hrs divided by 1.255 GW/hrs per year gives 3.953 years to cover the energy costs of making the silicon?."

payback = Four years???

So in a nutshell you get 3.953 years energy payback time assuming no losses in the best part of the planet, assuming no energy losses, that your silicon is at least 15% efficient?? and assuming no energy went into making the solar cell from the raw silicon.

I would put it to you Trevor, that making the raw silicon into a panel will double that figure, shifting the panel from the world's sunniest site on a cloud free high altitude plateau on the equator to a region far from the equator at sea level, like Sydney, would double that figure again as you'd no longer have the CONSTANT 1.4KW per sq metre solar flux I used in my calcs.

Finally a Telstra tech once told me that as a rule of thumb you get half the energy out of a battery as you put into it, so your figure would double again, so 4 years x 2 x 2 x 2 = 32 years assuming your batteries never die, your inverter is 100% efficient and you solar cells never age. If you could use/sell your solar power at the 24 Volts it makes without needing to store or convert it you would still have a payback of about 16 years.

The only commonly available cell on the market with any real usable performance WILL have this problem....regardless of what marketing tells you Trevor. There are experimental cells of different design but they are not available retail yet.

It sounds like you've been listening to your solar cell retailer Trevor, over it's lifetime, an alternator is environmentally less polluting to manufacture than a solar installation but would pollute more if run constantly all day instead of when needed, which I thought your use would be?.

Regards Mark Harriss

Reply to
Mark Harriss

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