How big of a solar panel array would you need for a machine shop?

[the gman]

Just idly thinking about what what happen in the event of a loss of grid power and while I intend to have a residence equipped with sufficient solar to power our needs, I got to thinking about the shop. What say the experts in the field when it comes to a lathe or a mill running 220V? I would think you would need a helluva battery backup to provide enough energy for them no?

Obviously I wouldn't run more than one of them at a time but it got me thinking. Sometimes that's a good thing, other times not. If not solar, then what? Steam running on coal (shit ton of that in this area) or how about tapping into a NG well site as my prospective piece of property is bounded on two sides by well sites? I've heard well sites produce NG at very, very high pressure so it can be difficult to reduce that down enough to usable household supply pressures. What say the collective?

[Nomad, 2nd]

My home is offgrid.

Been living here 3 years and lived offgrid in my airstream significant portions of other years on site.

It would be too expensive.

The batteries alone to handle 220....


It could be done, but it would be more affordable to position like they did back when.... Hydro.

[easttex]

You didn't mention if your machines are single or three phase.

What I would think about, were I looking into this is what kW demand does my shop require when I use my tools and how much do I need them. Knowing about how many kW is required for how many hours will help you figure out how many amp hours you need available and would also help you size up your solar array.

On the flip side of the coin, and for probably far less money, you could install a generator that you'd only run when you need the shop available and you'd have power available in all weather, day or night, as long as you have fuel. The single or three phase thing would be easy to tackle with a generator as well.

As to NG wells, I'm not sure you can tap them. I grew up in the NG fields of Eastern Texas and I'm not familiar with any current landowners utilizing their own NG wells. But I could be wrong about that and the regulations may be different in New Mexico. Some NG wells are high pressure, some are almost played out and have low, intermittent pressure. Some produce quality gas and some produce a mixed mess of gasses you wouldn't want to deal with. I'm not sure I would consider tapping local gas wells as part of my energy backup plan.

[frankxtc]

Might not be too weird.
There are plenty to 220 volt inverters.
To get one w/ the amps needed is some $$$$.
Need lots of golf cart batteries, wired to produce 48 VDC.
How many solar cells you need depends on how many batteries you have to be charged in a day.
More batteries, more PV cells.
If your shop is like mine, the mill or lathe do not run at the same time (just me here).
And I don’t typically use a machine for very many hours at one time.
Most jobs are less than an hour of making chips.

So I would cut until the batteries were at the discharge limit.
Shut down and do more work the next day, after the batteries are filled up again.
Repeat as necessary.

[medicmike]

What about using a smaller solar and battery array to handle lights and smaller tools and a generator to handle the higher amperage stuff? I think this is the way I would approach it.

[the gman]

Yeah, I was engaging in idle speculation as I plan my future house in my head. We used to have plenty of land owners out here who were provided with free NG from the wells on their property but Conoco-Phillips stopped that about 5 years ago, paying them off with $50K each plus installation of alternative means. (hooking into new NG supply lines or propane)

Friend of mine bought 14 acres with a well site right in the middle of it and the gas company gives her free propane for life. Its a part of the contract and is transferable and enduring.

I intend to have a partial grid tied system with a supply of Edison batteries to allow us to be self sufficient if we need to be but have access to the grid for the shop, high drain items etc. I'm also planning on a Kohler propane generator but was wondering about the possibility of tapping into the well site if absolutely everything went to shit. I'm aware of the issues with impurities in the gas supply but both sites have donkey engines working so that might be a possible point of access.

This is just speculation and blue sky planning because I just can't see this republic holding together for much longer once Trump leaves office, whether that be 2020 or 2024. The socialists in this country will be trying their best to destroy it and something is going to give. I'd rather be prepared to take drastic measures than be left hanging with good wishes.

Wife and I were watching a home show the other night and they were touting the undoubted benefits of a smart home with all the utilities connected via the internet. You could adjust the lights, temp and even the master bedroom blinds from your cell from anywhere in the world. Which is great until either someone hacks into it or the internet goes down in a TEOTWAWKI incident. Then what? Told the wife we won't be building that shit into our home; simple switches and thermostats have worked for decades and still will, even if the internet is DOA.

If we get hit by an EMP, well, we're gonna be fcuked and that's the end of that but I think that is the more remote threat. Global economic collapse is what concerns me or, as referenced in the other thread, a pandemic that cripples the globe. A good clean field of fire and other, energetic physical deterrents should assist in keeping the hoards at a distance when coupled with a relatively remote location.

[easttex]

^^^Which is why I miss rural East Texas so much and can't wait to bail out of the Metroplex and live far away from such a large target.^^^

[Invictus77]

FWIW - A diesel engine will run on something like 85% natural gas. It must have some liquid fuel for lubrication. I would assume that would be true at some level for propane as well but my only experience was with NG.

[12v71]

Originally Posted by Invictus77

FWIW - A diesel engine will run on something like 85% natural gas. It must have some liquid fuel for lubrication. I would assume that would be true at some level for propane as well but my only experience was with NG.

The diesel fuel wasn't so much for lubrication but for ignition. There were many old 2-stroke Detroits running on NG that used a "pilot injector" to supply diesel fuel for an ignition source with out spark plugs. The later Detroit series 60 NG engines used a magneto and spark plugs with no need for diesel fuel.

Cummins also ran their engines on NG with a mag and spark plugs. Of course all these engines require a gas mixer on the intake system.

[John A]

If you have a 220 invertor, you could let your car and alternator run it.

You wouldn't want to over-stress the batteries though, but short spurts probably wouldn't be too bad.

But as has been said, the batteries are what's going to cost you out the wha-zoo.

[Invictus77]

Originally Posted by 12v71

The diesel fuel wasn't so much for lubrication but for ignition.

Learned something new!

[BamaFal]

Thought about steam power? I have tried to learn somethings but I am no Huey!

[meltblown]

A metric shit ton. I’d get a stand by generator with 500 gallons of diesel to keep the lights on till I skim the grease trap in the septic system. No natural gas connection here. Nor water. You won’t freeze to death or drown. Most methane isn’t going to work when the compressors on electricity

If you can afford batteries on a solar grid then GFY. Here it would be to keep a fridge running and a ceiling fan.

[RG Coburn]

For what you're doing,I'd either run those machines straight from an engine,or get a PTO driven genny and a diesel tractor,and run off that. You could also just buy a big genny. Solar wouldn't be that great to run it.People around here get solar,not to really run their house,but to sell back into the grid,to offset their power consumption. Most don't have batteries.They invert and dump into the grid.

[the gman]

Originally Posted by meltblown

A metric shit ton. I’d get a stand by generator with 500 gallons of diesel to keep the lights on till I skim the grease trap in the septic system. No natural gas connection here. Nor water. You won’t freeze to death or drown. Most methane isn’t going to work when the compressors on electricity

If you can afford batteries on a solar grid then GFY. Here it would be to keep a fridge running and a ceiling fan.

The two well sites closest to the land I am looking to buy have NG powered engines to keep the gas flowing, no electricity required. I'm going to be in a position to do all this because I got injured on the job and my body hurts every damn day. I'm never gonna be able to do the things I used to do like skiing, hunting in remote areas or even dance with my daughter; helluva price to pay for getting what I want huh?

[hueyville]

I have a 5,000 square foot facility with 4,000 square feet of shop space with a 8"z×50"y×100"x running a three phase 30,000 rpm 7 h.p. Perske high frequency spindle motor which requires a 25 h.p. 3 phase vacuum hold down, dust collection system and often the 30 h.p. 3 phase air compressor system running all together. Recently sold my 60" tool room lathe and shopping for a smaller 36" CNC lathe as not the manual machinist would like to be. Am more of a software designer who converts to G Code and send it to a CNC machine. Also looking for a medium size HMC and why got rid of the huge Sharpe lathe and Bridgeport to make room for some CNC.

Know a lot of folks running three phase off single phase with a phase converter but seems convoluted to me as always having to be careful which tools are running so don't over tax their phase converter. I work with generators, batteries and solar in professional environment for Ma Bell as a subcontractor and to run a 48 volt DC switching site size of a 20 foot shipping container requires $20,000 to $100,000 in batteries just to keep the phone equipment running the ten hours required by FCC, Homeland Security and 911.

If ran solar would not use minimal in tandem with batteries and use a grid tie system to run my 120 volt single phase needs selling my excess to electric company during the day to offset night time use, rainy days, etc when have to suck back from the grid. Have three gasoline generators that have tri-fuel kits and run fine off natural gas or propane. Would consider buying a surplus or new natural gas generator if have access to free natural gas and use for shop plus sell its overage plus top off batteries that would run an LED lighting system.

I have wind turbines in storage as the noise was driving neighbors nuts. Sound like turboprop airplane engines running when wind is up. Solar panels are expensive or every roof in every city would be covered with them and batteries tied to them instead of big sets of Generac or Caterpillar generator systems. Around me all our peak load electrical generator sites are natural gas. I would sign a gas rights deal with a gas company where they built the infrastructure and provided you with a tap for gas at pressure you need. Then install a 1.5 to 2.0 Kw Generac single phase generator to your home and an appropriate size three phase generator or single with phase convertor for shop. Have enough batteries or small generator for lights and ancillary equipment when not running machines for lights, computers, etc.

Would tie all to the grid for when machines are broken with grid tie inverters so energy would be going into grid when making overage and sucking off it when need. It's going to cost a small fortune so need to figure watts on all equipment down to your toaster and coffee maker. Figure out lifetime energy needs and cost per kilowatt hour to just buy electricity for your lifetime (I use age 84 as doubt if live pat 84 will be doing much work. I have yet to figure out how to make power cheaper than I can buy but do not have potential natural gas well in the yard.

All I am concerned with is adequate emergency power for grid down situation and burning natural gas or diesel are most cost efficient means for me. Do you know any geologists or electrical engineers you can lean on for advice. Household use will be easy to average based on square footage but shop will be highly dependent on equipment and run time. Can have $275 power bill if out of town and work is slow and $1,500 if busy and leave CNC running 24 hours a day running tool paths with vacuum holding part and air compressor feeding mist coolent system.

When power is out and start pouring diesel fuel to the diesel generator can burn some money in fuel to keep three phase hot and with my generator have to be careful about running too many tools at same time. Talk to geologist, neighbors, electrical engineer and a gas company to see if can work a deal on fuel. Running big machines for long off solar and inverters doubt you could recoup cost of total system in 50 years. Could use for your low amp devices but big machines when go 240 volts will be expensive. May want to consider 480 volts as is much more efficient.

[the gman]

Originally Posted by hueyville

I have a 5,000 square foot facility with 4,000 square feet of shop space with a 8"z×50"y×100"x running a three phase 30,000 rpm 7 h.p. Perske high frequency spindle motor which requires a 25 h.p. 3 phase vacuum hold down, dust collection system and often the 30 h.p. 3 phase air compressor system running all together. Recently sold my 60" tool room lathe and shopping for a smaller 36" CNC lathe as not the manual machinist would like to be. Am more of a software designer who converts to G Code and send it to a CNC machine. Also looking for a medium size HMC and why got rid of the huge Sharpe lathe and Bridgeport to make room for some CNC.

Know a lot of folks running three phase off single phase with a phase converter but seems convoluted to me as always having to be careful which tools are running so don't over tax their phase converter. I work with generators, batteries and solar in professional environment for Ma Bell as a subcontractor and to run a 48 volt DC switching site size of a 20 foot shipping container requires $20,000 to $100,000 in batteries just to keep the phone equipment running the ten hours required by FCC, Homeland Security and 911.

If ran solar would not use minimal in tandem with batteries and use a grid tie system to run my 120 volt single phase needs selling my excess to electric company during the day to offset night time use, rainy days, etc when have to suck back from the grid. Have three gasoline generators that have tri-fuel kits and run fine off natural gas or propane. Would consider buying a surplus or new natural gas generator if have access to free natural gas and use for shop plus sell its overage plus top off batteries that would run an LED lighting system.

I have wind turbines in storage as the noise was driving neighbors nuts. Sound like turboprop airplane engines running when wind is up. Solar panels are expensive or every roof in every city would be covered with them and batteries tied to them instead of big sets of Generac or Caterpillar generator systems. Around me all our peak load electrical generator sites are natural gas. I would sign a gas rights deal with a gas company where they built the infrastructure and provided you with a tap for gas at pressure you need. Then install a 1.5 to 2.0 Kw Generac single phase generator to your home and an appropriate size three phase generator or single with phase convertor for shop. Have enough batteries or small generator for lights and ancillary equipment when not running machines for lights, computers, etc.

Would tie all to the grid for when machines are broken with grid tie inverters so energy would be going into grid when making overage and sucking off it when need. It's going to cost a small fortune so need to figure watts on all equipment down to your toaster and coffee maker. Figure out lifetime energy needs and cost per kilowatt hour to just buy electricity for your lifetime (I use age 84 as doubt if live pat 84 will be doing much work. I have yet to figure out how to make power cheaper than I can buy but do not have potential natural gas well in the yard.

All I am concerned with is adequate emergency power for grid down situation and burning natural gas or diesel are most cost efficient means for me. Do you know any geologists or electrical engineers you can lean on for advice. Household use will be easy to average based on square footage but shop will be highly dependent on equipment and run time. Can have $275 power bill if out of town and work is slow and $1,500 if busy and leave CNC running 24 hours a day running tool paths with vacuum holding part and air compressor feeding mist coolent system.

When power is out and start pouring diesel fuel to the diesel generator can burn some money in fuel to keep three phase hot and with my generator have to be careful about running too many tools at same time. Talk to geologist, neighbors, electrical engineer and a gas company to see if can work a deal on fuel. Running big machines for long off solar and inverters doubt you could recoup cost of total system in 50 years. Could use for your low amp devices but big machines when go 240 volts will be expensive. May want to consider 480 volts as is much more efficient.

None of that will work where I am looking to buy. The power company doesn't have 3 phase available even though the power poles are right on the edge of the property line. Not going to be running anything crazy, just a 220 lathe and mill, possibly a 220 table saw and a bunch of 110 stuff like drill press, band saw etc.

No gas companies in NM are currently installing gas lines from the well to residences. They used to do that but they did a risk assessment and didn't like what they found in terms of potential for liability so they paid off all the existing contracts and won't do new contracts. In addition, I don't want a well site on my property. Having worked around the oil and gas industry a few years ago, it is extremely disruptive to the property, noisy, smelly and a blight on the property as well as devaluing it. Screw that.

The electric company servicing this area is a micro grid utility owned by a local city. They do not want, encourage or appreciate solar power generated by households so offer little to no net metering, credits for installing solar nor incentives to do so. Doing these things would cut into their profit margin and I'm not getting into solar to have the cheapest power possible. I'm doing it because the property is over 5 miles from the nearest paved road and once you hit the blacktop, its nearly 10 miles to town. I want to be self sufficient for power in the event of an economic collapse when the local power workers ain't gonna turn in for work so the power goes out with little to no prospect of the lights coming back on anytime soon.

What happens then? Propane/diesel generators will run until the fuel runs out then what? I'm making an investment in the future energy security of my household because I'm fairly convinced this charade called modern life is gonna come crashing down at some point in the near future. I don't need 100 AR's or one more firearm period. I have enough toys to defend the homestead already along with enough ammo and a plan to do so.

The house I am planning is going to be incredibly energy efficient with solar water heating (both domestic hot water and radiant floor heat) and high efficiency mini split AC. Walls are 8" ICF, roller shutters for all windows, commercial steel doors, LED lighting, tight construction, etc. I have been planning this house for a LONG time and they will carry me out of it feet first.

This was kind of a "wonder what would happen without power" kind of thing because sooner or later, its gonna happen. FYI, you couldn't pay me to have a Generac POS generator anywhere near my house. Friend of mine works with them and he says they burn up real quick whereas Kohler have a stellar rep. There's a reason Generac have fancy ads and they sell them at Home Depot because they are cheaply made and the profit margin is huge. Thanks for the input.

[easttex]

I hear exactly what you're saying and you're doing what I would do, given the opportunity.

Solar panels have a 20 year service life. Inverters usually don't last that long and neither do batteries. Do you intent to keep a stock of replacements in inventory once those you initially install reach their end?

As an aside, you may need to verify that inverters can be stored long term. I'm thinking they have large electrolytic capacitors in them like VFDs do and if so, the capacitors dry out and smoke if you don't use them.

[adam762]

Not hard. Single phase 220 off an inverter will be fine. Use it to run a rotary inverter for the three phase. Good clean REAL 3 phase for multiple machines, at once. Just gonna need lots of batteries. I’ve got a rotary I run off single phase and it’s perfect. I’ve given this a lot of thought as well.

https://www.ebay.com/p/American-Rota...d=370774922286

Here is one. It’s rated up to 20 hp. So, if you know that you have a 3 hp motor on the mill, and a five hp motor on the lathe, and a five horse power motor on the air compressor, you know that you can run all three at the same time. It’s really not hard to not overtax the inverter. And it sounds to me like the only real homework you need to do is figure out what method of storage to use. You said that you want to generate using solar most likely, and that’s great. Battery selection and quantity is about all we really need to figure out. The best battery for your situation might be rather different than the best battery for my situation. But battery storage is the biggest question for those seriously interested in being independent.

[the gman]

Originally Posted by easttex

I hear exactly what you're saying and you're doing what I would do, given the opportunity.

Solar panels have a 20 year service life. Inverters usually don't last that long and neither do batteries. Do you intent to keep a stock of replacements in inventory once those you initially install reach their end?

As an aside, you may need to verify that inverters can be stored long term. I'm thinking they have large electrolytic capacitors in them like VFDs do and if so, the capacitors dry out and smoke if you don't use them.

Actually, in doing a lot of research, it seems modern solar panels are warrantied for 20-25 years but life expectancy is in excess of 40 years with a moderate reduction in capacity. A tracking solar array is preferable to a fixed array and here in NM, I get at least 300 days of sunshine so access to rays ain't a problem like it is in other parts of the country.

I've been doing a LOT of research into Edison batteries and many of them are still going strong all over the world, many of which are over 50 years old with plenty over 70 years old. It appears if they are maintained properly, regularly serviced and monitored, I could expect a long, long life out of them. They will stand regular deep discharge cycles that will kill lead/acid batteries in short order and unlike lithium ion batteries, have a long lifespan for a little less money. They are more expensive than L/A batteries but I'm not interested in doing solar on the cheap. I'm about longevity because I can't pay Huey to come haul a truck load of batteries out of a hole in the ground on a rotating basis of several years.

I'm gonna have to research the inverter storage issue though; hadn't considered that so thanks for the heads up.

[adam762]

George, if you don't mind me asking, what kind of time to break even on your investment are you seeing with your planned equipment? Reason I ask is I have no idea how long some of this stuff lasts. Your comments on solar cells warrantied for 20 years, and diminished production out to significantly longer is the first I've heard of things lasting that long. Additionally, the life span on those Edison cells is incredible. My biggest concern with a solar investment is that by the time the investment pays for itself, the equipment will be worn out and broken. But maybe not? I understand you may be willing to pay a little more per kilowatt hour for your own 'fresh squeezed' juice, because you control it, and I'll be in that boat too eventually but right now I'm still in the suburbs. Just looking for some augmentation. Until I buy my 60 acres down in Pike county....

[RG Coburn]

Edison batteries! That's it. I was trying to think of what somebody posted on these a while back.

[the gman]

Originally Posted by adam762

George, if you don't mind me asking, what kind of time to break even on your investment are you seeing with your planned equipment? Reason I ask is I have no idea how long some of this stuff lasts. Your comments on solar cells warrantied for 20 years, and diminished production out to significantly longer is the first I've heard of things lasting that long. Additionally, the life span on those Edison cells is incredible. My biggest concern with a solar investment is that by the time the investment pays for itself, the equipment will be worn out and broken. But maybe not? I understand you may be willing to pay a little more per kilowatt hour for your own 'fresh squeezed' juice, because you control it, and I'll be in that boat too eventually but right now I'm still in the suburbs. Just looking for some augmentation. Until I buy my 60 acres down in Pike county....

Adam, I honestly haven't put the pencil to it in an ROI equation. I'm budgeting around $50 -60K for the solar set up, exclusive of solar heating with evacuated tubes. I think Huey said it best: if you're looking to ensure a secure supply of power for your home for the next few years, a standby generator with NG as the power source, might be the best investment UNLESS your utility offers some kick ass incentives for solar that make it worthwhile.

My own locally owned utility have essentially kicked people like me in the balls and refuse to give any kind of real incentive for being energy generators. Their idea is that if I grid tie my system and become energy independent, sending excess power to them and drawing power from them say at night, making my electric bill virtually zero is a bad thing. Their reasoning is that if I'm not paying anything, all the associated costs for power generation, transmission, maintenance and other costs will fall on the shoulders of the customers who aren't willing, able or otherwise in a position to become energy independent. Ergo, they want to bill me at almost the same rate as every other customer while selling the green energy I produce at a premium rate to other customers who choose to pay extra to make them feel good.

While I can't argue with them scamming the dumb asses who buy into their bullshit, I'm aggravated I have to pay almost the same as everyone else while reducing the overall amount of power they need to produce. Hardly fair or right but hey, that's my local city all over. Here's an example: the local hospital went out and purchased a shit ton of solar panels with tracking stations so they would be super efficient. They wanted to put them on land they owned by the hospital that had a clear view of the sun all day. They applied for a permit to install the panels and the city council voted to not allow the installation! One of the councilors claimed she was worried that the land adjoined land she owned and the installation might reduce the value of her land... Can you say conflict of interest?

Well, this dick move on the part of the council was front page news in the local rag and people were pretty pissed about it. Plenty of folks called, wrote and emailed the councilors to let them know they were unhappy with this boneheaded decision and the next month, a vote on it was rescheduled and passed easily. Small town politics, gotta love it...

To get back to your question; I know there are some areas, as in TX, where there are companies who will install the entire system for you, lease it to you and they reap numerous benefits from the system sufficient for it to make it worthwhile for both of you. Example: you pay the company, they install it, you lease it. Company guarantees your lease payment will never rise above the amount you save by not buying electricity from the utility. In order for this to happen, the utility has you agree to not draw power from the grid between certain hours and to produce X amount of kwh per day. Leasing company is getting benefits from tax incentives, payments from the utilities and so on. Win, win, win.

There is a house builder in AZ who is building solar into their new homes on a similar plan but with a twist. The are installing a system into their sub-divsions that can be controlled by a central command and offers the potential to be a huge battery backup for the local grid. Great idea and here's a link to the article:

https://www.jlconline.com/how-to/ele...tery-systems_o

This is the future for many people but I'm still looking at total economic collapse so their model doesn't work for me... You might check and see what your utility offers to see if that twists the ROI back in your favor.

[hueyville]

I am not talking about Generac from the home improvement store. Am talking the kind you see behind a government building, private surgical center or hospital. Storing enough solar overage in batteries to run a house and a shop is going to tap five figures easily. Have average monthly power bill at house down to $85 with peak use being June through August. Building a tight heat envelope is your best friend and LED lighting another big help.

Have you priced imverters? For sensitive electronics will need true sine wave inverters and a name brand Samlex 3,000 watt inverter costs a grand. That will run your entertainment center and a computer. A good 3,000 wattt modified sine wave inverter with transfer switch is $1,200. Solar panels, batteries and inverters to run an entire house with HVAC plus a shop would expect six figure cost pretty easily.

[the gman]

Originally Posted by hueyville

I am not talking about Generac from the home improvement store. Am talking the kind you see behind a government building, private surgical center or hospital. Storing enough solar overage in batteries to run a house and a shop is going to tap five figures easily. Have average monthly power bill at house down to $85 with peak use being June through August. Building a tight heat envelope is your best friend and LED lighting another big help.

Have you priced imverters? For sensitive electronics will need true sine wave inverters and a name brand Samlex 3,000 watt inverter costs a grand. That will run your entertainment center and a computer. A good 3,000 wattt modified sine wave inverter with transfer switch is $1,200. Solar panels, batteries and inverters to run an entire house with HVAC plus a shop would expect six figure cost pretty easily.

If Generac is content to sell shit that bones consumers and sell the better stuff to .gov, then they are an unethical company that doesn't deserve my money. I spent a week interviewing and working with a UK generator company in 2001 when they wanted a new general manager and saw how quality units are built with no shortcuts. That's the kind of company I want to deal with not some assholes who are content to put out cheap shit for the masses while treating others differently. I lost out to a former Sgt Major as they thought he had more command experience than I did. He failed and when they came back to me, I had already moved on. https://www.dalepowersolutions.com/about/

This was a hypothetical question to generate (no pun intended) discussion. I've budgeted 5 figures for the system or did you miss that? Of course I priced inverters along with the rest of the system. No, its not going to be cheap but sometimes you got to bite the bullet and invest in something you want for energy independence. You obviously missed the part where I talked about a very tight house with ICF construction, LED's and high SEER mini-split AC units, conditioned crawl spaces, high efficiency appliances, well above industry standard insulation and so on. This is going to be my final house and I anticipate living here for the next 40 years if the creek don't rise and I don't expire before then...

I'm trying to figure out how to run the shop long before I get to build it, buy a single machine or move the first spadeful of dirt. That's because the British Army instilled in me the 7 'P's' 30 years ago: Prior Planning and Preparation Prevents Piss Poor Performance.

No point building a nice shop then finding out when the SHTF, you need a part for some vital piece of kit and have the machinery to make it but no power to operate the machine... Solar might not be the solution to run the shop full time but that's not the aim. Its for those times when I might need to make a shaft or mill or weld or cut something. Until or unless the world goes to shit, it will be running on utility power. The backup generator is for short term outages but solar will run the house with the batteries overnight and on those rare days we don't get much sun. When the grid goes down, we will have power unless its an EMP attack and then we're all screwed...

[hueyville]

Caught all the high efficiency features your building into the home. My concern is solar panels running a small/medium machine shop. Went to school and am certified to do Energy Audits and suggest how to impliment Green Energy solutions in existing structures or plan into new construction. Also state and Federally licensed for HVAC, MVAC, low pressure ammonia coolers, household electrical, commercial electrical and even explosive environments. Do a fair amount of equipment maintenance in explosive environments as have all my liability/workman's comp insurance along with OSHA from lock out/tag out through HAZWOPR.

My most enjoyable service do for folks are energy audits where use thermal imaging to find all leaks in heat envelope, calculate energy draw of all devices and cost to upgrade each and every system from weather stripping to replacing windos, HVAC, etc and calculate how many years takes to pay for a more efficient anything then based on its lifespan expected savings. It's really odd how long it takes to recoup cost of systems many tout and how much average homeowner can save with simple solutions like spending a weekend with a case of expanding foam sealant, a few batts of insulation and a desire to save money. Have a inexpensive heat loss detector can aim at walls, electrical outlets, door jambs, window seals and homeowner can borrow to do work themselves based on my audit, hire me or a handyman.

Install mini splits all the time when people have issues with an area of structure that's always hot or cold compared to rest and forces them to run main HVAC system when just need to heat or cool the master suite. Many ultra high efficiency heat pumps are service nightmares. For our climate generally install Tempstar Dual Fuel HVAC which can run as high efficiency heat pump or run as gas furnace when need suplimental heat and R510a.

Have a local guy who owns a well drilling company so cost to drill wells is just fuel and equipment wear. Drilled two wells that pump water back and forth to scrub the constant temperature water for cooling in summer and heating in winter which maintains a constant 55° temperature year round thus scrubs all his cooling in summer from just the energy to pump the water back and forth then run fan on air handler. It keeps his house at its 55° in winter with a heat pump providing the small amount of extra heat needed.

Trenched a yard and buried a lot of pipe for a ground coupled geothermal coupled HVAC system but it was not cheap but he looks at it as a lifetime investment for him and the next owners. So many ways to skin cats and preheating your hot water with solar is cheap but for convenience sake we went with a natural gas instant on tankless water heater. The electric units suck and for our HVAC, water heater amd other devices purchased the propane conversion units when purchased each system. If natural gas grid goes down then can swap all my orafices over and swap all to propane and suck off our buried propane tanks for some time.

If have money to spend a ground coupled geothermal system works anywhere and will be posting a quote from a site I visit where a guy who is a bit of a guru from AZ runs his ground coupled system at nine feet deep.

http://www.greenbuildingtalk.com/Des...9&attachid=272

http://www.greenbuildingtalk.com/Des...9&attachid=273

http://www.greenbuildingtalk.com/Des...9&attachid=274

Just going deeper isn't the cure all.
There are a lot of systems out there both vertical and horizontal that have been "short looped" by the installer.* Meaning there is not enough pipe in the ground.* As the heating season progresses, the loop temp keeps dropping until the incoming water temp is below the capacity of the heat pump and then the unit locks out.* Then when the cooling season starts, the loop temps keep climbing until it is higher than the capacity of the heat pump and the unit locks out.* Needless to say, these folks are not happy with their systems.

My house has a 4.5 ton heat pump.* I have 6000' of slinky pipe buried in my yard.* I dug trenches 9' deep by 1' wide and dropped the slinkies in.
I did not at any time work in a 9' deep trench.* It is now the end of January and my loop temp is 42°.* The loop temp in October after heating the ground all summer was 55°.** Since my heat pump can handle incoming temps of 30°* and 90° I am doing quite well.* The swing from 55° to 42° is largely affected by surface temps since the top of my loops have 5 - 6' of cover.

So having said all of that ...is it better to put your loop deeper ?* Maybe, you have to consider the cost and the safety factor.* It is against the law (OSHA) to work in a trench deeper than 5' with out some kind of trench protection.* Or you can taper the sides of the trench.

The graphic ( see above post: ground temps2.pdf) shows that for 5' deep the temps swing 20° and at 10' deep the temps swing 10°.* So by going 5' deeper your loop should be 5° warmer in the winter.* How much is the increase in COP for 5° warmer water?* I don't know,* but not a lot. In looking at my heat pump manual, COP at 40° is 3.84 and 30° is 3.45.* This is a difference of .39 COP for 10° warmer water.* So 5° would give you an increase of about .2 COP or about 5%.

So is digging 5' deeper for a 5% more efficiency worth it?* Let me know what you think.

As to Generac have a contractor grade 7,500 watt, 10,000 watt surge unit purchased 26 years ago that has run our house through many a power outage plus regular testing including many that last four to five days and one that lasted ten, it runs non stop and never had an issue. Has a trifuel kit and runs off gasoline, natural gas or propane, just turn a knob based on fuel feeding it. Till we did the addition, added the new HVAC system which we use to keep main floor, garage and basement it kept up but now struggles when HVAC starts up in A/C mode had to add hard start kits to my motor run capacitors and other devices so when cycle on the extra capacitor takes a lot of stress off the small generator. Was going to pull this off trailer and pad mount behind house. If at work when world goes sideways will hook to the big truck. Load an extra six barrels of diesel fuel on truck along with all the gun tools, parts and other critical tools, spare motorcycle or three then use the 28,000 pound GVWR 6×6 with Cat engine to push my way the eight miles home.



It's a four cylinder diesel three phase but is really too much for house, loud though intended to pour concrete walls around it, add sound dampening insulation and be happy because I traded some tower work for it but being stuck to diesel only and stealing my work three phase doesn't seem like a great idea. Tight as we run the ship could get by with a 10.000 watt, 12,500 watt peak generator but going higher just because I can. Install mostly Generac commercial at Ma Bell sites and have decided to add a GENERAC*GP SERIES 15000E in generator she'd which is a portable contractor grade machine with 1.5 Kw of constant power and 22,500 peak load watts, convert it to tri-fuel, tether to natural gas and mount next to the 7,500 watt machine to have as backup or to pull a heavy cable to neighbors in emergency.

Have two 2,000 watt inverter generators in garage with pairing kit. Can run separate with 2,000 watt continuous and 2,200 watt peak or pair them for 4,000 watt with 4,400 watt peak. If the new generator that will be here before winter sets in takes a dump can run HVAC, freezers and fridge off the 7,500 then run home entertainment and lights off the inverter generators as have ability to split my electrical system. I will be sucking off the grid rest of life as Georgia Power is a good outfit with whole house surge suppression for an extra $10 per month. The battery stacks are no good without a way to recharge and on cloudy winter days, especially if coated with ice or snow solar panels do me no good. Our batteries are for running silent if need and to run while deciding if power will be out long enough to warrant firing generator.

If lived in the desert where had tons of sun and warm weather would already be a solar sucking baby. I don't want to cut back my huge oak trees with ten foot plus diameter trunks, pecan trees or my magnolias nor Spanish holly. To properly load roof with solar cells would have to lay waste to my shade trees and in North GA sitting in the shade sipping sweet tea is a lifestyle. If had more property would put wind generators back up but far enough from my and other homes didn't bother folks with their noise. Can change pitch of props and quiet them down but loose power output.

Brick exterior, black board and plywood between brick and studs then spray foam insulation is super efficient. Have hurricane rated storm windows with 3M Ultra Prestige security/thermal window film which just the film adds 30% thermal efficiency. Then it's energy efficient dual paned glass windows with security window film then polycarbonate ballistic liners inside for Windows that are more energy efficient than most exterior walls. Another project is to e I the use Dryvit or Synergy EIFS to add another inch of foam to basement wall thats not underground and coat with synthetic stucco to tighten up basement just another smidgen.

Have R30 fiberglass insulation over ceiling of main floor then rafters have R22 stapled between. Then between 3/4" tongue and groove decking on roof have a layer of tar paper then two inches of styrofoam under metal roof. Did that at shop and gas bill dropped so significantly the gas company came and inspected the system to see if had rigged it some way to spoof the meter. Their accusation upset me enough told them to take their meter and have a 1,000 gallon propane tank backed up by a 500 gallon tank.


Have these security rated dual pane high efficiency storm doors on all exterior doors which really seal up the doors super tight plus add more security before able to attack main doors.



If want to go off grid can do it about anywhere in lower 48 based on how hard you want to work and what your budget is. Pay about $1 per watt for solar cells as can get 300 watt durable panels for $300 each. Need about two watts per square foot of home thus a 2,000 square foot home will need 4,000 watts of solar panels if have good sun and rotating system that tracks angle of sun. Your panel racks if ground mounted can rig a tilting rack system for pretty cheap with a little ingenuity. Seem people span 20 foot sections of steel tube on large wire spools and manually turn as needed to get max exposure. Other have rigged decent sun tracking panel arrays using garage door openers. Longer the panel is oriented to get full sun more watts per day. If have a big field could trench your geothermal coupled HVAC then sit panels in same area and have double duty in single area.

Then it's getting your power to charging system, into batteries for nights and low sun days. Inverters matched to equipment running, some will do fine on lesser expensive square wave, others stuff on modified (most will work on modified) square wave then a large true sine wave or three for your sensitive electronics. Much of this can be shielded from all but the strongest EMP. Good grounding, surge arrestors, Faraday cages in equipment rooms or in tight metal building properly grounded and your rocking. I SHTF rules will change on the Ponderosa and solar panels have scrounged over the years will come out of lock and key along with the wind turbines. Have enough solar and wind to keep a small electric car charged or batteries sharp for critical equipment when generators would draw too much attention. The small inverter generators will run inside house vented outside quietly enough won't raise any attention and keep critical stacks sharp if wind and sun doesn't cooperate.

The big capacitors will keep voltage from stacks up, inverters power devices, and can keep even one or two rooms cooled with portable A/C units. I have to have electricity for health as my BiPaP ASV must run, will be wanting to run oxygen generator as well for when people feel bad. Also want radios, cameras and electric fence powered. I would like to see how much power could squeeze out of 5,000 square feet of solar panels on roof of shop. Five figures, say $35,000 to $60,000 should stack out a nice solar system. Will it run your shop? Calculate watts every machine and device munch, how much they will be run, do your math and see if panels will feed watts to batteries, if have enough batteries to store it and remember need a grid tie inverter to match phase with the grid so you can sell any overage batteries can't store to your power company as its law, they have to buy it. Suggest hiring an EE for planning.

[FIANNAFAL]

A quick rule of thumb is for every Amp of AC, you need 10 Amps of DC going to the Inverter.
Larger Generac gensets gave me the least amount of problems, while doing PM for TxDot in south Texas.

[adam762]

I'm still in the early stages of learning. George is much farther along than I as are others it appears, and I am appreciating the info. I am NOT at a stage where I can budget 5 figures for this, so I am looking for components that I can pick up over time to build a functioning system WHILE its functioning. If my first generator is a relatively crappy unit from home depot that I bought for $250, and my first inverter and panel set is a crappy unit I bought from Harbor Freight, and my first couple of batteries are QUALITY Iron Edison units, then I can put a small backup ability in my house sufficient to run the basics in the summer and everything in the winter. And I can save for a better generator, and buy more batteries, and better panels, and all do it over time, with the batteries always being the constant.

[easttex]

This is the kind of thread I really enjoy because I always learn something.

[davedude]

Bought my first four panels from Sunelec back in the day, 60w 12 volt. They had the best prices then and I think they still do. Think pallets of panels and the price goes down to $0.30 per watt or so. For you guys looking to go big that's the way to do it.
Electric utilities everywhere are hostile to homeowners generating their own power. They will try to make you jump through hoops to sell them excess power. Screw them.
Edit to add: Federal tax credits are available for solar installs but I think they might be going away soon unless they have been extended again. Last I heard the tax credits would end in 2019 or 2020 which is why I invested in upgrades this year to make my shitty little system less shitty.
For you guys doing a small system with battery back up don't make the mistake of going 12 volts or even 24 volts. Make your battery bank a 48 volt one as you can size inverters much larger and get higher power than with the lower voltage ones.
I went all Outback on my inverter and charge controller with the Mate system controller and Hub to tie them together. I like the many different modes of operation the Outback inverter/chargers offer over the competition. I have a Midnite Solar Epanel for the big DC. breakers and interconnect wiring.
I maxed out my panels with four more from fred480 on eBay. Had to carefully match voltage with the existing panels I am keeping, kinda a bitch to do but necessary so I don't Rob myself of power or have panels fighting each other.
The Outback inverter/charger and 60 amp charge controller I got from solarhome.org who blew away everyone else's prices.
I got my Haticon racking, Use2 wire and other stuff from some outfit called solarelectricdistributors but had to fight them to get my orders. Ridiculous low prices though so was lucky but I can't recommend them. Can't get Haticon racking anymore looks like.
MC4 connectors from Renogy Solar. Blue Sea Systems for the battery bank switches and 250 amp fusing on each bank. I can switch each bank on to or off the big DC buss.

[davedude]

While I am thinking about it you got to have safety disconnects, bypass and transfer switches all over. After the combiner you need a safety disconnects that can handle the job under load. Disconnect high voltage high current DC and you can get the mother of all arcs so get the right gear. And label them correctly, specific labels are required to identify the critical ones.
Soon everyone will be forced to have a single button or birdcage device that first responders can pull to disconnect the whole system automatically at once so check your local laws.

[Wecsogery]

Originally Posted by Invictus77

FWIW - A diesel engine will run on something like 85% natural gas. It must have some liquid fuel for lubrication. I would assume that would be true at some level for propane as well but my only experience was with NG.

Propane works too, as does home-produced methane.

Originally Posted by John A

If you have a 220 invertor, you could let your car and alternator run it.

You wouldn't want to over-stress the batteries though, but short spurts probably wouldn't be too bad.

But as has been said, the batteries are what's going to cost you out the wha-zoo.

Nope. Car alternators are a terrible way to generate power. They're unbelievably inefficient. And car batteries aren't much better.

What I would do is find a 71 series Detroit Diesel genset. There are lots of them out there, and they turn up for sale all the time. Most of them can be wired for single or 3 phase, or a combination of both. They will run just fine on filtered and heated waste cooking oil or motor oil, mixed with diesel or heating oil in any ratio if you have it, and/or up to 10 percent gasoline. Then you can add any gaseous fuel you might have in a dirt-simple system of simply injecting the gaseous fuel into the air intake stream. Basically put the minimum continuous load on the genny (charging your battery bank, powering your lights, filling your water tank, preheating water etc.) and open the gas valve, watching the fuel rack gradually close as you add more gas, until it's at 20-25 percent. Then head into the shop and start working.
The engine's governor will automatically add more liquid fuel as needed, when you add more load.

Buy the correct motor oil by the 55 gallon drum. It's cheaper that way. The stuff you use in a 4 stroke diesel is not what you need for a Detroit.
When you change the oil, add the spent oil to your fuel storage.

[Wecsogery]

Originally Posted by frankxtc

Might not be too weird.
There are plenty to 220 volt inverters.
To get one w/ the amps needed is some $$$$.
Need lots of golf cart batteries, wired to produce 48 VDC.
How many solar cells you need depends on how many batteries you have to be charged in a day.
More batteries, more PV cells.
If your shop is like mine, the mill or lathe do not run at the same time (just me here).
And I don’t typically use a machine for very many hours at one time.
Most jobs are less than an hour of making chips.

So I would cut until the batteries were at the discharge limit.
Shut down and do more work the next day, after the batteries are filled up again.
Repeat as necessary.

This, too. I would get the generator, but also get a 220V inverter as a backup. Either get one with the same input voltage as your main battery bank, or just build a separate 48V battery bank for the shop. Complete with its own panels. An 8000 watt inverter will work fine for up to 3 hp motor, with power to spare. A 3 hp motor will use 3300 watts running under a heavy load; call it 3600 to account for inverter efficiency. 1 hour of operation under that kind of load will draw only 75 amp/hours from a 48 volt battery bank. So eight golf cart batteries in series for 48 volts will run your small shop for about an hour and a half while remaining within the upper 50 percent of capacity.

That's not too bad. But here's the bad news: four of the solar panels that are sold as "100 watt," wired in series to charge your 48 volt battery bank, will take about four sunny days to recover from that hour and a half. That means you will need 16 of those panels to recover in one day.
Just to clarify a bit, those panels can actually produce 100 watts... but your batteries can't absorb all of it. Maybe 70 percent of it. That's just how batteries work.

[hueyville]

My advantage is free batteries, wiring, connectors, racks, 48 volt power plants and abilty to scrounge. All of my solar panels are in storage and won't go back up until grid goes down as are my wind turbines. It's actually much less headache to keep my batteries topped off by grid or my regular cycling of generators to keep them from seizing due to sitting too long without cycling. Keeping panels cleaned as leaves, dirt, moss/mold and debris buildup around here causes them to lose inefficiency quickly if don't go out and wash them regularly and keeping gutters and roof cleaned is enough work for me. All I need is emergency power for,short term and then a plan for minimum needs long term if grid collapses.

Give solar a decade and we are going to see industry catch up to what people want and expect at a price can stack all the panels need. For now it's still a technology for people who can either cobble together a lot of bargains and install the systems themselves or who can write the check just to be hip or thumb their nose at the system. I can buy energy so cheap with good energy efficiency practices keeping the batteries in place and maintained with energy output devices stored makes more sense. House bill averages $85 per month and 5,000 square foot manufacturing facility is $150 to $300 unless run welders for extraordinary number of hours or CNC router 24/7 for days on end.

[the gman]

Rebooting this thread after speaking to a good friend of mine who has worked in the gas fields all his life. He showed me exactly how to tap into well sites for free natural gas if I ever needed to in extreme emergency when the world has gone to shit. So, I got my answer about running the machine shop in the event of TEOTWAWKI; buy a standby generator which runs on propane with the necessary hardware to turn it over to NG when needed.