SoCal off grid living

[CharlieEscCA]

Enjoying my 8 kW DC grid tie ground mount system that has been running for a week -- that someone else is likely going to enjoy

I've just entered escrow on a 12+ acre property. SDG&E service is about 1600 ft away (at the lot next to me) from my likely building site on the land. There is closer service, about 400 ft down a fire access road to another neighbor, but per SDG&E I would need to obtain a new easement from the owner (there is a general "utilities" easement dated 1969, but SDG&E says they require an easement naming them directly) -- I will be talking to this neighbor seeing if a "let's make a deal" arrangement can be struck.

But in the worst case, the 1600' route, a builder guestimated up to 50K to get bring power to the building site; talking to SDGE, they ballparked 20K paid to them AND I have to have a contractor trench the 1600' and lay conduit and set a pad for the transformer all too their spec -- I'm will be working on getting an estimate for this in the week ahead.

But, this all brings us to the question of whether one should bother to spend 35K to 50K to bring power, and then more than likely spend 15K to 20K on a solar installation vs just spending X to go off grid. Because this will be a new build, I'm thinking it will be built such to much more efficient than my current house (which actually other than A/C does quite well, and A/C is bad due to really high vaulted ceilings and several leaky windows (the nature of the window design) -- the new house is likely going to be foam block concrete and a very tight building envelope,

I like the idea of the ultimate battery bank of the grid, but at what cost? Comments???

P.S. I was going to hold off until 2019 to build, but too much uncertainty interest wise and what CA local and state laws will change to make building even more costly and hard. Hence, get a design done now, get my house ready for sale, sell and build (sell will be before house is ready to move in; done the own two house drill once; county allows temp mobile home / fifth wheel on property while building -- that plus shipping container for storage of goods and I'll be all set. 2019 might have helped battery technology wise but perhaps not.

[SunEagle]

It may seem like the up front cost to bring the grid to your home is high but the cost of a battery system to support your home is also high to begin with and continues to cost every few years to replace. Based on previous installations I have seen costs for a solar / battery system fall between $2000 and $3000 per kWh and most homes will consume about 20kWh a day. That could be an up front cost of $40k to $60k.

Based on the current cost of new batteries, they can generate a kWh for about $0.50 to $1.00 which is usually a lot more then what you can purchase that kWh from the POCO.

You really have to run the numbers to see what it is going to cost you either way. IMO until energy storage costs come down by a factor of 3 it will be cheaper to purchase the electricity from a POCO then to generate it from a battery. Don't forget to add in a generator to charge those batteries when you have multiple days of no sunlight.

If you still want to install solar then go with a grid tie system. At least the solar panels will pay for themselves over X years compared to a battery system which more than likely will not ever pay for itself.

The choice is yours to make but if it was my money I certainly would do the math to see what is a better financial direction.

[peakbagger]

You definitely are on the rare edge of where a OTG solution may make sense. Is a bank going to be involved? If so they may not give you a choice as many banks require utility power for mortgage. Even if you are working on a cash basis (I applaud you if you are) Is this your forever home, I.E. do you plan to be buried in the back yard ?. The reason is that if you ever plan to resell it you have instantly cut 95% of the potential interested buyers (who may need a mortgage). Are you and whomever you live with willing to adjust your lifestyle to the available power? Some folks just swap masters and replace the power company with the propane company. Are you and the whomever you work with "handy" and have basic electrical skills?. Off grid systems are not plug and play, sure there may be skilled firms with great staff that can come and build you a system and maintain it, but the reality is the technology changes and the pro that you rely on may not be there five years from now and bringing in someone not familiar with the system is going to be an exercise in frustration. Ideally you and whomever you live with have to be in the loop enough to be able to troubleshoot and maintain the system yourself. Expect that no matter how well a system is designed today, five years from now parts of it are obsolete and you may need to change out equipment. You can reduce the impact by making sure that you run extra conduits and leave plenty of space on your power panel but expect that in addition to routine battery replacements you will have unexpected equipment change outs. By the way, a generator will be in the mix, stuff happens and at a minimum you probably need a power source for equalization. Don't skimp on a generator. Many folks advocate a high reliability portable like a Honda but others advocate a fixed automated unit.

There is no ultimate battery bank and there most likely never will be. Battery technology is changing and will change rapidly. On the other hand flooded lead acid battery's have been around for over a hundred fifty years and are pretty predictable. Treat them right and they have predictable life spans, beat on them and they will also predictably fail. That's why many long term solar folks advocate "starter batteries" for your initial system as most folks, despite the best intentions, screw up and kill their first set of batteries. Feel free to look at nickel iron just realize that you are chained to the house to keep them full of distilled water.

Speaking of water, the biggest load for many folks is their well pump. If you have spring or permanent water source cascading down the mountain great but if you have a deep well pump it can suck a lot of power in short period of time. There are deep well solar pumps, but they are not cheap and unfortunately they don't violate laws of physics, they are more efficient than typical multistage centrifugal well pumps but need to be integrated into the design.

There are several schools of zero net energy designs optimized for certain climates. In New England, Passivhaus is the hyped standard as its oriented to high heating zone areas. The Pretty Good House is a Vermont based concept which basically goes for Passivhaus energy use with far more conventional materials and techniques. I expect there is similar design in your area. If you go with a near net zero home, inevitably its going to cost little to heat and cool if its designed correctly but if its a DIY be aware you wont get 100% right the first time around. A general comment about foam block concrete is that its fallen out a favor in some areas as a conventional poured foundation with proper insulation on the interior of the wall works as well and is less expensive. There is also an issue in the northeast that carpenter ants love to tunnel into foam and create nests and passages directly into the home through foam/concrete blocks. In areas with less ant issues, the foam can go outside which adds the concrete into the household thermal mass. Ultimately whatever system you go with, the devil is in the details, if you DIY you can ensure the details are done right but if a contractor is involved they will take shortcuts. I know of few folks who have had net zero homes built and they spend a hour or so every night after the contractor has cleared out with a can of foam just filling in potential cracks.

Good luck with your decision

[LETitROLL]

Your per month KWH usage now (and expected at new house) are powerful clues to lead you in the right direction. Size and scale of the solar route are big factors in overall upfront cost and of course long term cost. The grid has a fixed up front cost, solar power systems do not, if you can save enough up front with solar by living with the limitations of a certain budget (20k system) then it may take a while for the grid to "catch up" , otherwise without significant conservation and/or super efficient new house (all gas appliances, etc.) you don't want to spend 30-40k on a system plus more per KWH or you will fall behind quickly and forever more, not to mention the babysitting and repairs, outages, etc. remember with off grid you also get a new part time job at no extra cost.

[jflorey2]

But, this all brings us to the question of whether one should bother to spend 35K to 50K to bring power, and then more than likely spend 15K to 20K on a solar installation vs just spending X to go off grid.

Let me give you a third option. Get a small off-grid hybrid system - and then use one of your neighbors as a "generator." Offer him $100 a month or something* for the ability to use a 120V or 240V 15A circuit. The reason off grid solar is expensive is battery cost, and you need large batteries to deal with times of no solar available. By having 1800 watts available at all times of the day and night the size of your pack is drastically reduced - and since it will never see low states of charge (due to reliable recharging being available) it will last a lot longer.

If power goes out or he doesn't pay his power bill or something, fire up your generator while you figure out what to do next.

You will still get _most_ of your power from the solar array, but with the backup power available, your system will become more of a generator-assist system than a full blown off grid system. You'll save a lot of money over a full blown off grid system, and your neighbor will make a little extra money. (And the cost of running a buried 15A line is far lower than running a 200A service.)

(* - or put in a meter and pay him 50 cents/kwhr or whatever.)

[J.P.M.]

Did you know where power was when you bought the property and how much it costs to run a line ?

I had similar circumstances about 8-10 yrs. ago. SWMBO & I own 10 acres in Borrego Springs. I designed, with the help of an architect, what was going to be my residential solar magnum opus out in the desert.

Power was at the edge of the prop. and the run would be ~ 600-800 ft. I had ~ $10K + $75/ft. in the prelim. est. to run service. For a lot of reasons, I gave up on the build, but it did get as far as plan review w/the county. One of the big, but not only reason the project was stopped: Turns out builders who want to work in Borrego Springs are few and those who do don't want a lot of owner input/surveillance. If I was in their shoes, I might feel the same about it. Anyway, that's off topic.

With ICF construction and CA title 24 mandates, expect a very low building loss coefficient. If you are not familiar w/ Title 24, I'd respectfully suggest your sit down, say to yourself "This is going to be a PITA on conformance hoops", get a copy of Title 24 start reding. You can curse the wind, but that code will just about force you to do a very energy efficient design. FWIW, and IMO only, most of it's requirements are cost effective even if the energy ignorant don't understand them. Just sayin'. I'd SWAG it'll add to the construction costs by maybe 10 % or more and add more than 10 % to the PITA factor. It is want it is.

As for any PV, I was planning for grid tie. There was never a question of any off grid electricity for my lifestyle, except maybe a generator for power outages lasting longer than a day or so. I like the idea of no umbilical electric cord, but that concept is mostly a charade for most folks. I'm a realist in the sense that I'm not about to go off grid and pay for the alleged freedom in lost time and maint. requirements. Besides, keeping the same lifestyle and going off grid would probably cost as much or more than running grid access and I'd still have a large maint. cost and probably more PITA. The way I looked at it, I want nice, I pay nice. I just try to walk in w/ my eyes open.

My design was planned to be tighter than Title 24 mandates and, while not ICF construction, have a lot of thermal mass -actually more than ICF. Once built/occupied, I was planning to accumulate a yrs. worth of use history before getting a ground mounted PV system installed. FWIW, initial energy requirements for ~ 3118 ft.^2 building put the initial PV size at ~ 7-8 STC kW. The HVAC load estimate was quite small for the climate due to the construction and the small winter heating load was designed to be met w/propane. The design would have included a solar thermal water heater. Doing it now, I probably would have scrapped the solar thermal, bumped the PV by ~ 1.5 kW STC and gone w/ a heat pump water heater, but maybe not, as quiet is a big deal to me and thermal collectors are still quieter than heat pumps.

[CharlieEscCA]

Did you know where power was when you bought the property and how much it costs to run a line ?

Haven't bought quite yet In escrow; sent the wire transfer for the deposit today; 20 more days where I can cancel at no cost; in the complete "investigation" phase now.

I actually had been putting together cost estimates for the last month -- but working hard to double check numbers and make sure there are no other gotcha's I missed accounting for.

Interviewing an architect today at the property -- see if it's a fit personality and budget (his fee and overall budget in mind.

Unless there are big surprises, or budget numbers blow up, I'll be closing June 1.

[Sunking]

Last thing I would do is to build an Off-Grid home in a place like San Diego. You would never be able to sell it. Even though rates are high in San Diego, long term cost of Off-Grid is still going to be many times more than the local POCO even with the up front building cost. Not only is th ePOCO much less expensive, but is a lot cleaner source of power. There is no upside to Off-Grid.

[J.P.M.]

Haven't bought quite yet In escrow; sent the wire transfer for the deposit today; 20 more days where I can cancel at no cost; in the complete "investigation" phase now.

I actually had been putting together cost estimates for the last month -- but working hard to double check numbers and make sure there are no other gotcha's I missed accounting for.

Interviewing an architect today at the property -- see if it's a fit personality and budget (his fee and overall budget in mind.

Unless there are big surprises, or budget numbers blow up, I'll be closing June 1.

Off grid seems like a nice idea to many folks, most of whom seem to be ignorant of what off grid requires. Hovever, once people find out the true cost in time/$$/hassle, including new batteries every 5 or so years, their enthusiasm is dampened.

That $50K for adding grid access you write of may well be a bargain once you find out the $ cost difference between an off grid and on grid system might cost, not to mention the lifestyle adjustments of the Grizzley Adams variety that may well be required to make even a frugal system viable and cost effective.

Suit yourself, but homework and investigation will usually lead to better information and more informed choices. Not all of the off grid consequence is bad, but most folks seem to have no clue about what's actually required. It seems that it's more than an unplugged romp in freedom from an electrical umbilical cord.

Just walk in with your eyes and mind open.

[bcroe]

Let me give you a third option. Get a small off-grid hybrid system - and then use one of your neighbors as a "generator." Offer him $100 a month or something* for the ability to use a 120V or 240V 15A circuit. The reason off grid solar is expensive is battery cost, and you need large batteries to deal with times of no solar available. By having 1800 watts available at all times of the day and night the size of your pack is drastically reduced - and since it will never see low states of charge (due to reliable recharging being available) it will last a lot longer.

You will still get _most_ of your power from the solar array, but with the backup power available, your system will become more of a generator-assist system than a full blown off grid system. You'll save a lot of money over a full blown off grid system, and your neighbor will make a little extra money. (And the cost of running a buried 15A line is far lower than running a 200A service.)

(* - or put in a meter and pay him 50 cents/kwhr or whatever.)

In these parts it would be illegal for me to sell electricity to anyone. I certainly wouldn't risk my grid tie contract
to do that. As much as I would have liked to give some free surplus KWH to my neighbor,there would be a
risk if anything went wrong. I did think about suggesting he plug into the outside outlet on my nearest
building. Bruce Roe

[Mike90250]

Feel free to look at nickel iron just realize that you are chained to the house to keep them full of distilled water.

Bah. I just got back from a trip to town to refill my zero ohm (distilled/DI) water jugs. Only 5-6 gallons every 2 weeks.

I run a 2 story, 2000sf house, wood heat, no air conditioning, propane for cooking & hot water. Washer, dryer, 2 adults. 2 fridges, 1 upright freezer. Not counting the irrigation pump, we average 7Kwh daily in winter, 9kwh in summer. All appliances are energy star, but one fridge has un-cleanable coils in the base (they run side to side and can't be brushed out)
PG&E threw every trick in the book at us, 3" conduit, with approved pull boxes every 100 feet, or their certified poles, and we'd have to plant them, then PG&E would inspect them. Because of the distance, we got 2 transformer pads (apparently 9 years ago, nobody made a 6Kv - 240V transformer, so we needed 2.
So it was a much easier choice for us to go off-grid. Summer, we irrigate, and pump about 3,000 gal daily.
Our water is from a pond, pumped to elevated tanks on sunny days, and gravity feed to run everything. drinking water is filtered via a Slow Sand filter, and stored in a 1,500gal tank with a ozone bubbler in it http://www.tripleo.com/