Back to the OP...
You've got really two prime characteristics here...
First being lousy power company service...
Second being 3phase demand.
The grassroots approach to power WILL work... Neil's comments, and others' suggestions and recommendations should be taken as food-for thought and further research on your part. With proper conservation approach, and development of a generation and storage system, you could be largely self-sufficient in respect to domestic power need, without grid connection. One could also use utility power as backup when your primary renewable source is offline, or your prime mover (wind, hydro, PV, etc) isn't available.
The three-phase demand, however, is a totally different echelon... your figure of 100kva is not certainly not unattainable by grassroots approach, but the economy-of-scale of windpower makes a commercial 'mill much less expensive. I'd say call the folks at Vestas, Clipper, etc., and see what you can find on the used market. Present-generation windies are in the 2-3 MEGAWATT range, and run multiple PMDC generator units feeding big inverters. Previous generations (like the 35kw Vestas mills) are on the market in the under-$100k range... and will get you enough power to run big tools, as long as the wind blows.
I'll agree with Neil's notes on intertie connection, but with caveat. Our midwestern states' utility boards have their own rules, and said rules allow utility companies to establish THEIR OWN interconnection limitations and requirements. Presently, MY utility company's rules effectively prevent consumer-level interconnection, and there's no level of compliance that can be done until one's power output capacity not only exceeds a certain threshold (in the megawatt range), but also, must be guaranteed (meaning, when there's no breeze, I gotta have other generation on-tap). Even with that done, I'm still bound to installing expensive switchgear.
Until suitable legislation overturns this rule, running a non-interconnected system is totally out-of-the-question, as if they FIND me doing it, they're totally within their right to yank my utility service altogether.
This may seem totally ridiculous, but from one perspective (the power company's), it maintains their control over their power system, and makes them exclusively responsible for whatever it takes to guarantee my power availability and quality. It prevents electric anarchy.
So to cut to the chase...
I'd say have 'em drag in their sissy utility feeder. Set up your 3-phase system either using rotary conversion, or put VFDs on your machines. Set up your farm with emergency/auxiliary generation using a combination of renewable systems, as well as backup with at least two stages of fossil (low and high-power fossil fuels), and make the farm as energy-efficient as possible. I've been doing this for the last few years...
Now... Use the money you saved... to improve efficiency. It'll keep adding up... and scout the market for rebuilt 2nd and 3rd gen commercial windmills. Once you've got a commercial-grade up, use that as your prime-mover, and use that money saved to purchase and install more. Once you have a group of 'em, section off a viable number of 'mills, and then challenge the local utility with an intertie option. Dedicate those machine strictly to feeding the utility, so your home/shop isn't in the economic middle. If they slap you with switchgear requirements, write for a government grant to help pay for switchgear installation, or find a local philanthropist to partner. Use the power-generation revenue to pay for your mills, and buy a few more and additional switchgear. If they lever you with 'minimum generation guarantee' requirements, find a small fossil-steam plant that'll give you a guarantee contract to take your place when there's no wind.
In doing so, you've effectively grown to be an Independant Power Producer. Invest in some modern megawatt-class 'mills to change out your 'wimpy' old 3rd-gen units... up your output, THEN go knock on the utility company's door to bring 3-phase to you, and see how they treat you.
Thinking about this further, how about some sort of hybrid system?
1) small utility feed to the property for backup.
2) energy storage in lead acid batteries, solid state inverters to convert to ac.
3) wind generators which feed the batteries.
4) a larger prime mover three phase generator for large
three phase needs.
So the wind powers the batteries, when the wind isn't blowing
the utility can keep them charged. Small three phase loads
can be via VFDs from the battery buss.
The most obvious thing about a wind turbine is the cube law power........ 1/2 wind speed gives 1/8 power. The rating is generally on a 28 mph wind, which you won't see very often.
Our wind clients figure about 20% of max average is good enough in many cases, at least for intertie "net power subtraction" usage, which is by far the simplest system.
There are two completely different types of intertie wind power, and they are getting mixed up in this discussion...
1) generation....... you are adding power into the grid. In that case, you would need the reserve generation etc, as they are adding capacity to lines to take your power.
2) "offset" or "net power subtraction".... where you generate on-site power which is ALWAYS less than your usage, so NO POWER ever goes OUT of your facility. No adder to any lines, your bill just goes down, and there should be no demand for reserve power capacity etc.
There isn't a huge difference, since either way the power supplied by the utility is variable over time. but when they add anything to take your power, they want to know your power is going to BE there. Otherwise that investment is useless.
BOTH ways you must have anti-islanding, all the rule 21 stuff, all the 1547 stuff, etc.
There is an installation right here at a construction company in St Louis, about a 30 foot or 40 foot blade circle unit, got used. It is run as #2, no net power out. We are not a net metering state, but Ameren UE allows it, and it has been operating pretty consistently. (I think it is out of service now, may have been damaged in a recent windstorm.)
Good thinking- since offgrid and intertie systems use different sets of equipment the project usually goes one way or the other to avoid the costs of both sets of equipment.
I think though, that viper's project and the huge loads he is projecting justifies the sort of multisource/equipment approach you're advocating. Gonna take some serious number crunching, consulting with a power systems engineer and the power company and maybe a different approach with the utility.
Dave- Excellent advice- I wish I'd written it. Utility attitudes and policies can and do kill utility intertie projects. Sometimes pioneering, intense lobbying, legislation and litigation are the only way to make it happen. I certainly don't have the dough to make it happen, and probably viper doesn't, too. Time for him to find the Lone Ranger or maybe a sugardaddy:-)
BillTodd- thanks for the praise and the link. The mantra " Location, location, location" is exactly right for siting wind turbines, too.