Thread: Shh.It followed me home.

Originally Posted by DonP

I am just glad that it managed to jump onto your truck and sit there unnoticed until you got home !!

...and it chained itself down as well.

I think we all know that sometimes tools just magically appear in our sheds by magic. The issue isn't "is it really magic?", its "if we all stand together and swear its magic will our wives believe its magic?" Because y'know if they began to suspect it wasnt magic we could all have problems at some point in the future. So yeah... it jumped up there, chained itself down and pulled its invisibility cloak on for the hundred miles home, and I was as suprised as anyone when I walked into the shed next morning and there it was sitting in the middle of the truck.

You believe me dontcha Don?

Originally Posted by ian

I like, though I was sort of wondering how you are going to get a 3ph, 30 kW motor to start, especially as I think you said elsewhere that your on a diesel genny. The starting current would be (what ?) 4 to 5 times the running current?

That mate is a real serious question. And the answer is I have a whole lot of other things to factor in , and I need to do a lot of thinking about the answer. And much of it is way beyond my electrical comprehension level. I'm giving a long answer in the hope someone comes along to read and maybe has some input.

Im not on a generator here. I was in a previous life, but that was cattle station type generators where the numbers were more around domestic power + workshop and the like which is a far more "normal" power load for most of us here with sawdustitis. Sawmills are a whole different ballgame in terms of current draw.

About 4 poles down the road from here we have the mother load of electricity - its a main transmission substation where the line from Kareeya Hydro Station meets the east coast network - so meeting the power requirements through the main shouldn't be a problem. However my existing transformer is only a 64 kVa unit. I have barely enough power there now: tablesaw/thicknesser/ bag dusty are no problem. Blower + 4 sider is okay provided you let each set of motors come up to speed before hitting the next switch. Blower + straight line rip (20kW) ... thats technically not enough for a star delta start but with a slow ramp on a soft start she makes it, though I've learnt to avoid certain times of day because of the power draw further down the local line, and to check the kiln settings to make sure its not about to kick in. If a compressor kicks in about then it throws the breaker on the 240v circut every time.

This one here would need around the 75kVa mark for star delta, better pad it a bit for the auxillary hydraulics on transfers etc which would require another 10hp or so motor.
Behind that there is the main bench. Its currently configured with a diesel power unit but if I'm going to enlarge the electrical system it would be better on electric too - that would be a 60kW motor.
The breakdown saw is also diesel powered but that one is best left that way. I dont have any intention of ever getting that big that I'd need it to run for more then a couple hours a day and I dont even want to think about putting that on electric power.
All these things need transfer decks and I need more compressor and...

200 kVa. Thats the part I get.

My issue lies around how to get 200 kVa: whether i'm better to get a bigger transformer or go with a diesel generator. 10 year fuel vs power cost debates, convenience issues, power quality issues etc etc. I dont know enough to know.
If I go with a generator am I better to embed and have it working on the same system as the grid power, or am I better to keep it totally separate. Now I'm really clueless.
If I go with diesel should I just put in a battery bank for the house as well and tell Ergon to kindly depart. (Thats problematic given my DH kilns so I guess thats out for 10 years anyway but I could be mostly grid free. Who doesnt dream of telling the power company to stick it?

Then theres the curve ball... theoretically we generate enough waste that if I installed a syngas unit in conjunction with the diesel generator we would be pretty much zero emissions/ carbon neutral. Syngas is classed as renewable energy, when hooked up to a diesel unit the engine starts and runs at idle speed on diesel but any power over that constant idle speed comes from the gas injection ( or not, depends which taps you turn it can still function as a straight diesel)
Figure that saves about 20 litres an hour in diesel fuel burn. I am very interested in that and not just for the financial benefit, which isnt really that great given gas production costs chew into the saving. I do feel most strongly that if I can run a sawmill on clean green power generated from my own waste then I should be doing so from an environmental/sustainability perspective. It also fits as my personal goal is to become the most efficient small mill in Australia.

I've got to find a way through this maze in the next 6 or so months, and while I can convert a generator to syngas later, there are some engines that suit that better than others. But I do need to resolve the entire grid vs generator matter, pick a way forward and go with it in the near future. We're battling... whatever we choose to do we'll be stuck with it a while.

Sorry for the long answer, but theres a lot of long term ramifications attached to starting this bench up.

What you are describing would, I think, elevate you to the status of a registered power generator within the National Energy Market. Which would mean that at certain times of the day/year you would get paid a "excrement load" to run your syngas generator.

I think you need proper "professional advice"

Originally Posted by ian

I like, though I was sort of wondering how you are going to get a 3ph, 30 kW motor to start, especially as I think you said elsewhere that your on a diesel genny. The starting current would be (what ?) 4 to 5 times the running current?

A VFD would probably be the simple solution. A lot cheaper than a 150KVA gen set.

Regards
Paul

Edit: realised I missed page two and subsequent comment. A variable frequency drive might still be worth a look however. Not sure how familiar you are with these machines but they can be programmed to start so gently there is virtually no starting current. You would require more than the hobby type unit for your situation. There is at least one industrial VFD specialist on the Forum and I can pass on his name for a PM if you wanted to pursue this avenue.

Of course I believe you !!

I chose to overlook the chains believing that you must have had to put them on when you discovered it on your truck. Woulda been dangerous to leave it lying there without anything holding it down. It mighta got itself lost !

DonP

Originally Posted by Bushmiller

A VFD would probably be the simple solution. A lot cheaper than a 150KVA gen set.

Regards
Paul

Edit: realised I missed page two and subsequent comment. A variable frequency drive might still be worth a look however. Not sure how familiar you are with these machines but they can be programmed to start so gently there is virtually no starting current. You would require more than the hobby type unit for your situation. There is at least one industrial VFD specialist on the Forum and I can pass on his name for a PM if you wanted to pursue this avenue.

Paul if you could do that it would be appreciated. I dont know much at all about VFD's... my understanding is its like a soft start but with a "volume" switch so you can adjust speed up and down manually rather then it being programmed in at the factory. I'm probably wrong. I'm up for a soft starter on this thing straight up, so nows a time to look at options.

Soft starts arent cheap. And what kills them usually is phase drop/brown outs through the transmission network. Seems that is becoming part of the future for all of us while varying governments and power companies squabble over who does what and for how much. That too is one of the issues I have to factor into this decision making process... how much can I rely on network power stability in 10 years.

Originally Posted by ian

What you are describing would, I think, elevate you to the status of a registered power generator within the National Energy Market. Which would mean that at certain times of the day/year you would get paid a "excrement load" to run your syngas generator.

I think you need proper "professional advice"

I do too Ian.I got to get this one right the first time and the cost of paying for advice is better then the cost of winging it (my usual strategy) and getting it wrong.

When I first started looking at this a couple years ago I "fell through the cracks". Its classed as small and renewable but not solar so the power co were not obliged to be interested, and not producing megawatts like the local sugarmill does with its waste to make it attractive to them. So I shelved it which is just as well because my power requirements have grown a lot since then.

I dont see it as getting the premium for peak delivery even though the energy market has changed since then. This is a lot like installing a wood stove - you get heat and hot water and cook with it from your shed offcuts, but you have to light the fire now so you can have a cup of tea in half an hour. Bigger systems are different but the usual economy of scale stuff puts that out of reach.

Gassifiers have been around a long time, but the convenience factor weighs against them.

How to build your own, plans issued by the US government: http://www.driveonwood.com/static/me...fema_plans.pdf

A modern small turn key automatic system: CHP energy; Renewable thermal and electric power; Borealis Wood Power Corp.

I often wonder how the police would react if they seen me driving down the road in my ute with smoke belching from the chimney, or pulled up on the shoulder tossing some sticks into the fire.