Michael Mobbs has been involved in sustainability for more than two decades, leading public discourse with his “sustainable house” blog, cutting his connections to mains water and sewer more than two decades ago, and finally cutting the electricity wires to his inner-Sydney terrace home in March, 2015.
His exploits and determination to lead a self-suficent lifestyle earned him the sobriquet of the “off-grid-guy”. But two years after cutting the link to the electricity grid, Mobbs is deeply frustrated – his off-grid system is not working anywhere near as well as he expected.
For the last few weeks, in cloudy, rainy Sydney, Mobbs has had to turn off the fridge during the day to ensure that the house, which he shares with two others, has enough power for a “civilised life” at night-time. Worse than that, his system has a bug in it that causes it to trip every two days. Flashing digital lights have become part of his life.
“I’m running short of power,” Mobbs complains. He reckons that the system that he has in place is delivering 1kWh a day less than he expected. “I thought this would be a walk in the park, but I appear to have tripped over.”
Mobbs in now looking to replace the system, and has even launched a public ‘invitation” for people to suggest solutions. (Submissions are due on April 13).
But he wants this to be a public discourse, because from his experience he sees a cautionary tale for anyone looking to install battery storage, and particularly those who are looking to go off grid.
“I don’t live off-grid just for myself,” he writes on his blog. “I live off-grid to trial and to show options, create and publish real-life data for others, to give hope through action and accountability. ”
But he admits that his particular journey for going off-grid for electricity is incomplete. “When complete, and the new replacement system is installed soon, the project will show what is feasible.”
Although battery storage has been used for decades, mostly in remote areas that don’t easily connect to the grid, the mass-market is new, and so are many of the products now available to those in the inner city, suburbs, and regional towns.
And battery storage is a complex business – it relies so much on the consumer’s usage pattern, available solar power, local weather, orientation and how it is configured and paired with other hardware and software such as inverters and solar panels. Going off grid requires a bespoke solution.
Some people have the money and can throw surplus dollars and capacity at the solution. Hobbs clearly wants to find a smarter way – and in the inner city, he is restricted by space.
Mobbs says that from his experience it is pretty clear that there is a consumer blind spot. He now emphasises the need to be clear about what is wanted from the system, and for good monitoring and analytics to indicate what is going wrong and when.
So what did go wrong with his system?
In 1996, Mobbs had solar panels installed, a 2.2kW system. In 2015, with a view to going off grid he upgraded his solar system to 3.5kW of solar panels, and installed 15kWh Alpha-ESS battery storage system with a 5kW Goodwe inverter. In all, it cost him $27,000.
At first glance, that looks about right. But it’s the detail that counts. Battery storage experts told One Step that Alpha and Goodwe are both good technologies, but they are best suited for “hybrid systems” which provides storage of excess solar capacity and back-up in case of a blackout. They are not the best option to be off-grid.
Mobbs also admits to not fully understanding the way that off-grid systems work. This graph (below) is an illustration. It shows the promised solar power (orange line), the actual panel output (green line).
It’s a huge difference, but it simply reflects the fact that when a battery unit is filled, any excess solar capacity is “spilled”, because there is no grid to send it back to. So the solar output needs to be carefully configured with usage and battery storage capacity. Some spillage is inevitable – unless you want to overspend on storage – because that is the nature of the beast.
“Remember: it’s the amount of power to be generated that is being installed and bought – not merely the things on the site,” Mobbs notes on his blog. “Merely having solar panels, inverter or batteries does not mean the anticipated amount of power is being generated (or stored).”
Mobbs reckons that with the extra 1kWh of available power he had expected he could “potter along”. He tells One Step: “So now I have not got enough. This month of rain in Sydney has given me over the horizon radar … it’s like Game of Thrones, winter is coming.
So Mobbs is looking to replace this set up and get a new inverter and battery storage. But he wants to make a few points clear about his experience, and the lessons to be drawn from it. The biggest lesson, he says, is the importance of data.
“What I am trying to do is tell the whole world, get good data and work out what you need. I am driven by data, I’m in the game of recommending products, but you have to be careful because you are not buying hardware, you are buying a promised amount of power. And if it doesn’t deliver, you need the data to prove that you haven’t got that promise.”
And data is important even for those who just have solar panels – some studies have shown that more than one third of all solar systems (there are 1.6 million rooftop solar systems in Australia) are working below par, often for some easily fixed fault, but the households simply don’t know.
“It’s not enough to say that we have got a lot of solar households in Australia. We have got to be able to say that they are delivering on their promise,” Mobbs says.
Other issues he has come across is the lack of a formal second hand market in solar panels. When he took down his original array, the installer didn’t know what to do with them. But soon enough, Mobbs found someone in the Blue Mountains who hopped in his ute to drive down and pick them up. He also wonders why there is not more recycled metals used in such systems.
Marlon Kobacker, of Sustainable Future Group, which has reviewed Mobbs’ problems, believes there must have been some communication break-down when the equipment was ordered. He says Mobbs has sized the system for around two or three days, when most people might size it for a week. And he doesn’t want a fossil fuel back up generator.
“In running the EOI process we doing now for either repairing or replacing system we are taking approach that we need be very clear with the brief up front.
“We want to get certainty round how system will perform, on the predicted output, and much better data interface … and to get smarter controls, load controls, and so at least there can be some sort of alarm when the system is heading towards a shut-down.
Giles Parkinson is founder and editor of One Step Off The Grid, and also edits and founded Renew Economy and The Driven. He has been a journalist for 35 years and is a former business and deputy editor of the Australian Financial Review.
This post was published on April 5, 2017 11:12 am
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Going off grid in the city is nutty - get a hybrid system and use a retailer that only sells green energy. Wasting all that solar is crazy, send it to the grid to offset some coal fired power in NSW.
Here's why it's nutty: http://www.solarquotes.com.au/systems/off-grid/
I agree. If you have generation that is surplus to requirement nearly all the time put it back into the grid and shut down a coal fired power station - please! Then, if you want to be rid of fossil fuels as much as possible but you use a car, then put as much surplus into an electric car as you can, but you will probably want the grid as back up for the car and house consumption. You could use the ATA's 'C3' greenpower to cover what you take from the grid.
How does Michael heat his domestic hot water and heat his house in winter? He could use all that surplus PV power to heat water for both purposes. Cheapest "battery" you can get at 50kWh/1000 litres.
I would agree that the equipment used is all ok technology, but there is 1 major floor in the design of this system, Given that you have 12-15kwh usable storage and a 3.5kw solar could only produce on average 14kwh per day, This poses the problem,how do you support the house load as well as put 14kwh back into the batteries, then add bad weather you may only produce 5-7kwh per day, then the basics go into a downwards spiral.
Goodwe GW5048D-ES will support up to 130% of its DC max rating 5200w dc this would give you around 7kw of solar input giving you around 30kwh average per day, 15-20kwh on the crap days.
this gives aroung 3000w for 5 hours to charge batteries, then carry the house loads with the rest, Bad weather you still may need to be a bit careful with the power usage.
Apart from being limited to a max 25amp house cicuit, it is possible to be off grid in the city, rather than chopping the wires to the grid it may have been better to have a manual changeover switch, for the just in case scenario.
This tech is at a point where you could operate grid free, but you have to size according to worst case scenarios, always use max amount of solar that the Inverter can handle, it will automatically ramp the system down if the power is not needed.
So if you added more panels to the exsisting set up most of your troubles would be solved.
regards
Michael Tournier
He apparently has a very low house load (like 5 kwh per day). Apparently the solar is being curtailed.
Even with a small house load, if the weather is bad a 3.5kw will only produce around 1.5kw maximum, this would give as little as 5kwh production per day, so a person may have an average of 5kwh usage per day, but it wont be exactly that, so the system will slowly fail to keep up. Also always take into consideration that if you take 1kwh out of a battery, due to efficience losses through cabling and charging you will need to provide 1.1-1.2kwh to recharge the batteries.
In the interests of unhappy customers, it would be always recommended to oversize the systems both in solar and Batteries. With the fact that solar will only produce about 50% in bad weather that should be calculated in to the design, especially if there is no back up from the grid.
Our family has run off grid on solar for over 25 years and I'm compelled to respond to this story. The system has been poorly designed. The practical reality of running a home off grid differs from a design like the Mobbs example that appears to have been based on largely theoretical computations. The reality is that an off grid system running on solar without backup from generator must function in ALL conditions. This requires greater generating and storage capacities designed to cater for the worst possible conditions including continuous rainy/overcast conditions. We have 11.4 KW of solar arrays and nearly 80Kwh (rated) of storage. We use Raylite 1160Ah lead acid cells.
Having sufficient solar capacity to 'keep up' during extended period of inclement weather, means that one will have significant surplus power during periods of optimal conditions. This surplus power (beyond maintaining battery charge and usage) should be stored in some other way. EG. Charging electric cars etc.
I don't understand the hype driven dialog suggesting that the cost of battery banks is dropping. We paid about $15K for our battery bank and were recently quoted around 100K if we wanted to replace it with the new technology (lower cost) batteries the likes of Tesla. From where I stand the price hasn't come down yet, we're a long way from that, with these new solutions still 5 to 10 times the price of existing and proven technologies. I believe the confusion stems from not understanding the difference between a grid connected system with some battery storage with a fully functional well designed off grid system. Cutting the grid connection to the former will lead to failure.
Li-ion lasts longer (more cycles and more years) than lead-acid, that's a *substantial* part of the price difference. "Cheaper" is cycle-life-adjusted among other things. Doesn't matter for your application, because for you it makes more sense to replace more often and have the money in the meantime.
I understand the advantages of LI, however in a situation where weight, size and maintenance are not an issue the LI is significantly more expensive even when considering life cycle. Raylite M-Solar batteries are capable of high cycling: ~3500 cycles to 20% Depth of Discharge (meaning your battery remains 80% full) and ~1500 cycles to 50% Depth of Discharge. Our 365 day average Depth of Discharge is %12.4. Perhaps by the time our LA bank needs replacing LI WILL be competitive. ;-)
I agree with you completely on your choice of battery.
IMO lithium is already competitive, it's just the application is wrong. A single Powerwall 2.0 will give you similar average performance (3500 cycles at 10 kWh) and cost the same as your 80 kWh system but if you use it as your sole source of storage off grid you'll be sitting in the dark every couple of weeks bemoaning your averages and how much spare solar you had last week. In the same way if you try and squeeze a 1500 kg lead acid block into you Sydney terrace plus and additional 20 solar panels you may go down in the estimations of your neighbors.
I don't want to be overly critical of the gentleman in the article though, getting as close as he has is a great achievement and probably involves significant modification to his and his families life style. My personal feeling is that what he needs is another source of power that compliments his current system. I assume micro-wind is out because he is in town, although if he is only 1 kWh extra per day this might be an option with a little more added storage and a seriously oversized wind turbine. He could also go with a small petrol generator modified to use ethanol instead of petrol. Bio-fuels aren't that bad if you only need very small amounts of them. A vegetarian living in Sydney using 5-6 kWh per day from solar plus 200 liters of ethanol a year (which gives 1 kWh per day average) would still be extremely low impact. You'd need about a 10 x 10 m^2 space in Queensland to grow that which is hardly the end of the world. Before the purest get on at me, I know you could make nearly 100 times the energy per year if you used solar but the point is he'd be low impact today not in 50 years time.
It would be good to know what your average daily usage is. It is fantastic to hear from someone who has lived off grid for so long. Do you have a generator?
The Li-ion vs Lead acid debate is always really interesting to me. 2 totally different batteries used in 2 totally different ways. IMO I think that for a 100% off grid property you are far better off with a lead acid system. I suspect that the 80 kWh system you describe never see's a full cycle and will get to float 4 out of 5 days. Capacity loss is probably not a massive issue because the battery is so large and probably only taken down towards it's lower limits 2 or 3 times a year which means the "longer" life (i.e. higher cycle life) of a lithium ion pack wouldn't really make any difference at all to you. IMO the lithium ion systems are really not well suited to the off grid duty cycle at all. They are much better living in a partial state of charge, regularly cycling and can charge/discharge at high C rates. This is far better for grid living where you want to displace as much grid power with as small a battery as possible. I assume there isn't enough space in Sydney for a 11.4 kW array and 80 kWh battery bank, I guess if the family is only averaging 5-6 kWh per day they could reduce the size of the system but for 100% coverage of your power usage I wouldn't have thought the size could be reduced by that much.
As far as I know, nobody publishes figures for battery life including a small number of really deep discharges per year (effectively using the forbidden DOD region as one's emergency energy reserve).
I agree. FYI: Past year average here: 18.47 kWh per day. Use all power efficient electrical appliances such as induction cooking, inverter AC and air sourced heat pump water heating etc. Use no other energy sources like gas. No generator, I sized the system so as not to ever need one (and haven't over three years). Our 'power station' is located about 600M from residence, also powers cottage, an implement shed and garage/shed with power tools including large compressor and MIG welding etc. The AC coupled inverters can deliver 19Kw peak in sunny conditions (7.5kw at night). We reach float at least 330 days in the year. Fully overcast today (yesterday and previous), float should be achieved by say 3PM, currently SOC = 98%. As to the Sydney installation, LA may be out of question (space, weight & maintenance) however following on with your thoughts of wind, a VAWT could be used to advantage in a city situation with disturbed air flow patterns.
Your system sound pretty fantastic. I rent at the moment but one day, when I win the lottery, I intend to build my own house and I think I would do something very similar to what you have done. 18.5 kWh sounds pretty good, I currently average around 22.5 kWh largely due to my electric car and my shockingly badly insulated rental property. The car is about 50% of my power usage. The nice thing about the EV is if you are short of power at home a few days a year you could always drop into a public fast charger... well at least I should be able to that by the time I can afford to build my own home. I reckon that will allow me to reduce the size of the system pretty substantially if needs be.
As for the VAWT, for Sydney. I wish I knew more about wind turbines. My feeling is that the high cut in wind speed required for most VAWT systems would make the turbine pretty useless in town, unless it was very high up. Personally I would probably go for a regular axis 1 kW machine but retro fit blades to it that are probably more suited to a 2 or 3 kW machine. This is pretty much what the big wind turbine manufactures do. They feather the blades at high speeds but I think the smaller systems just have a brake. I can't imagine inner Sydney being all that windy so there shouldn't be an issue with the turbine destroying its self and I am sure that you can get a system that will automatically feather its blades or change its direction if things got too hairy. I think it would be fun to try and get a wind turbine to work in town even if it only ever gave you 10-15% of your power. Anyway all good fun.
Thanks for sharing your system details
Chris
The problem here is that people are selling off grid systems based upon their on grid experience. They therefore take 'averages' when they should be looking at 'minimums.' The system above is drastically short on PV when compared to the amount of available storage and will absolutely fall over during overcast weather. A 10kW array would be pretty much the minimum. It would also have been good to leave the grid connected for a year (as an auxiliary charger), whilst the logging was analyzed.
Actually his existing system appears to have enough PV but is drastically short on batteries. Is that what you meant? The batteries aren't sufficient to last through a run of rainy weather, and the PV generation is getting thrown away in the sunny weather instead of stored.
In 30 years of installing Off-Grid systems only twice have I not used a back-up generator. Once for a small weekender cabin, and once for an experimental system for Dick Smith to test EV Off-Grid EV charging for his Nissan Leaf. Both were special cases, and I wouldn't recommend a normal Off-Grid install leave out the back up energy source. It makes no sense, unless you can go without when the batteries inevitably discharge below the minimum threshold. Every Off-Grid system needs a back-up unless it is massively oversized for periods like we are going thru in NSW were we haven't seen the sun properly for months. As much as we all want to disconnect from the grid, which I totally get, the grid at about $500 per year for access is the cheapest back-up generator you will ever buy and maintain.
And the grid also allows your excess generation to be used by others. The gentailers would have to make me very angry indeed for me go off grid - but I've always accepted that they may well be capable of inducing me to take that financially-costly if emotionally-pleasing decision
Everyone who cares about this issue should all lobby for fairer charges for the grid. A single pensioner who doesn't use much electricity probably pays more in grid access fees than for the amount of electricity consumed. The NSW Council of Social Service was very critical of these unfair charges in its submissions last to the Australian Energy Regulator.
We'll all suffer if unfairly high grid connection fees cause more and more people to consider disconnecting. The result will be a 'grid death spiral' where the costs of the unnecessary gold plating will are borne by fewer and fewer grid users. Low-income households who can't afford to install stand-alone power will suffer disproportionately, as will our greenhouse gas emissions if the surplus power from solar households isn't used elsewhere.
NCOSS submission: NSW Electricity Distribution Business Tariff Structure Statement (TSS) Proposals: NCOSS NSW Council of Social Services. Available at: http://www.aer.gov.au/system/files/NCOSS%20-%20Submission%20on%20NSW%20electricity%20distribution%20business%20Tariff%20Structure%20Statement%20proposals%20-%2026%20October%202016.pdf2016
So, let's get this straight. Key design points - currently using 4kWh/day, wants 5kWh/day. Does not want a backup genset, has only installed a 12kWh usable battery bank + a 3.5kWp PV system and wonders why he's out of energy? Probable causes (site unseen these are speculation of course) Item A - chances are that due to the inner city location the PV modules have had to be mounted parallel to the roof (probably 25 degrees pitch) rather than angled to optimise winter output (approx 45 degrees pitch at Sydney latitude). Not much to be done about orientation either I would surmise. So, energy generation compromised from the start. Item B - AS4509.2 calls for min 4-5 days of autonomy for PV systems without a genset, so at least 20-25kWh storage is required at maximum Depth of Discharge, not the 12kWh listed. Item C - A larger battery bank would typically allow for a higher charge rate, thus allowing the wasted energy to be stored. Item D - PV array of 3.5kWp x 2.2PSH (Sydney winter irradiation) x losses (approx for a PV system including tilt/orientation/shading/temperature etc) of 30% = est. 5.4kWh/day generation in winter without rain. That barely meets the daily load, oversizing of between 30% and 100% is recommended by AS4509.2 to ensure recharging within a reasonable time frame after a rainy period I'd be installing a minimum 7-8kWp (i.e. 100% oversized) to ensure recharge as quickly as possible within the charge acceptance constraints of the battery. Note also that a larger array would still be able to harvest most of the day's energy requirements even under reduced irradiation (i.e. cloudy days). Simple - the system installed did not conform to the basic principles outlined in the published standards, no wonder it's not performing as expected.
Expectations! The physics has a habit of ignoring these.
Trying to be solar and off-grid vrtually guarantees that you will be reduced to camping at home at least a few times a year.
My own experience is that the limited power budget forces you to make difficult choices in appliances. Difficult because the suppliers and retailers are totally clueless about efficiency. For example, asking for an efficient fridge invariably results in 12V camping units being shown.
I would have said that the production and storage graph actually looked not too bad, but some additional battery and charger/power tracker would be useful in the dark months - any days where the battery doesn't make it to 100% should take all of the PV output.
Several others have commented about the inverter. The maker conveniently only lists standby power, not "AC on, no load" power which would be a lot more informative and likely damning. My experience has been that the only inverters that have a good (25watt) ac on-no load figure are the big toroidal transformer types, such as those from Latronics. The transformerless types are more likely 50 or 60 watts; there's a good part of the missing kwh per day.
I completely agree with Finn etc.: In the suburbs, the grid makes a good backup generator.
Maybe it's easier to envision "camping at home at least a few times a year" from upstate NY, where the grid fails for at least 24 hours at least once a year so *we already know how to do that*.
I live with 2000W of panels for power, 300w of panels for led lighting, in a one person household with wood heating and hot water. I use a laptop, computer, coffee maker, washing machine, kitchen mixers and juicers, and I charge e-bike batteries twice a month. That's 3x20 a/h li-ions at 36V. My system has run almost without hitch for 6 years, with a $250 85amp Chinese regulator to feed AGM batteries of 24V, 512 a/h (4x256a/h) into a 3000W pure sine wave inverter with a 9000W peak load. That is a Power Star W7 (they make up to 12,000W, 36000W peak) which can still be bought for about $600.00 on eBay under various Brands. The only trouble I ever had with that was when my slackness caused water entry and I had to replace it with a Tomahawk branded version of same. Yes, in mid-winter I have switched off my top loading fridge(converted freezer) which I keep on the back veranda in the coolest spot available - but that was just because the outdoor daytime temperature was almost a low as inside the fridge. Just make sure that in mid-winter you still get at least four hours a day of unshaded sunshine (potentially) on your panels - trim trees or dynamite houses which block it - and all is sweet! The whole installation was under $10k for the self designed installation, with the 240 AC coming in via two builder's cords from the inverter outside. There is no fixed wiring except the DC 12v for lights and DC 24 volt for a sump pump in the cellar. If you have a house normally wired up with all lights and appliances running via inverters, you are using heaps of power in cable resistance and stand-by, etc., power drain. Adapt to a more frugal existence, take an active interest in your daily use, and learn how to enjoy every neighbour lighting candles when you don't know what an outage is!
https://uploads.disquscdn.com/images/547753c45550c8c3990d58c0076ac1ec4e5108124e00cacdf21974db5b296f08.jpg
Love the setup, interestingly, despite appearance, it is almost the same as the one in Sydney - although I suspect you have a considerable advantage in terms of using wood for heating. You probably get proportionally more power out of your ground mounted solar systems than the Sydney system but probably not 35% more but things aren't that different. I would suggest that both systems require far more adaption of lifestyles to make them viable than most people are willing to make.
Hi just Chris - ultimately adaption of lifestyle is the only viable option for most of us. I've been adapting for 35 years. I am happy and healthy at 68 (never see a doctor) and I am relatively wealthy, also, without power bills and low rates in a remote location. Wealth comes in terms of co-operative local community and low overheads, and relative lifestyles when compared to those who determine one's pension needs.
I would argue that the level of adaption that you have gone to is unnecessary to become sustainable as a society. We absolutely need to reduce waste and change the way we live but in order to become truly sustainable we need to cooperate on a whole higher level than you are suggesting - in short we need to find alternative sustainable ways of doing everything that we do as a society now rather than to stop doing what we currently do. With that in mind I think the biggest challenge that faces us in the next 10 years is a decoupling of physical growth from economic growth. This is a greater problem for economists than me as what I am suggesting results in all of their metrics they use not working. They struggle with the concept of economic growth being separate from stuff growth and with people being happier in smaller houses, with less stuff, using less energy, whilst still earning more money and creating more wealth but this is what will happen because people will find happiness in any future and the amount of stuff in the world is fixed - ergo we will find a way to be happy with less stuff. You'll hear people spouting on about efficiency and service industries but my feeling is that few actually understand what is possible when an economist marries a hippy.
You are right - and many ways have to exist side by side. We have to be willing to adapt as a society at many levels, not just in the rural setting. However, I believe that change will only come after major disaster. There are too many people in too many places who are almost welded to the past, and only great catharsis in the form of natural and man made tragedy will wake them up. Much major infrastructure may disappear in this process. I do wish I am very wrong.
I think there always needs to be an event to result in change but I don't think that needs to be a disaster, particularly with energy. The oil price spikes of the 70's and early 00's were sufficient to kick off renewable energy expansion and improved efficiency. Pollution in EU, Indian and Chinese cities has focused the minds of many and has resulted in greater push towards sustainable energy and transport.
There is much inertia in the system but that is not such a bad thing once you get moving. Wind and Solar are now big business and much like coal and oil producers will look to influence our governments to adopt favorable policy settings for their technologies, I think these 2 industries will seek to promote their own positions. This isn't corrupt or evil just a fact of life - If 10% of the population are employed by or dependent on the wind or solar industry they will sway elections just as coal miners unions used to in the UK 50 years ago.
There are numerous interesting things in this article
and the detailed discussion below but one thing that leapt out at me as a potentially rapidly expanding gap and
opportunity is the lack of a secondhand market in solar panels, and perhaps related gear.
Is this worth some detailed examination? I think it is.
I bought 180W panels in perfect working order in Sydney for $50 each, advertised in Gumtree last year. At perhaps 6 years old they should last another 20 years.
When people have to fix their roof, they pull off the old panels and then realise that new panels will give them 270W and the panel capital cost ($172 a panel) is only a small part of their new roof cost. The latest panels give 360W (but extra cost).
Exactly, at these prices not one roof square metre can be wasted. They can be used to power daytime loads even when residents are not there (pool, hot water) and fewer electrons would be used to top up a battery.
Firstly what a great article!
Being a fellow "Gone Off-Grid in a City" person and having read about the system Michael had - interested to read his comments and those of others. I would add that I do not have any form of backup power - if you want this, just pay the connection fee to the grid and turn it off unless you need it! (Cheaper and quieter than any other form of backup system)
From reading all of the comments below - there is one thing I think we can all agree on is that there is no "Magic formula" to successfully going off the grid. Location, Day vs Night Usage, Summer vs Winter Usage, Roof Space and how hacked you off with the Energy Generators and Distributors are all factors to consider if thinking about "Going off the Grid"! And even then - there are days where you wonder if Going off the grid was such a good idea!
Also I make a distinction to being "Off the Grid" vs "Going or Gone off the Grid". There are a lot of purpose built homes that are designed from the ground up to be energy efficient and "off-grid" or by their very location, they are designed to be "Off the Grid" as the local power was expensive to connect to.
The first question I ask people who want to Move off the Grid is "how prepared are you to change the way you use energy?" if the answer is not really - we just want to buy a system that will sustain us in exactly the same way that the grid does - then I hope you have a lot of space / money and luck.
Then there is the technology issues and options, solar panels, hybrid inverters and then there is batteries.... another conversation where you can ask 5 people and get 6 opinions! (proof below! - and all people having great advice too)
What is changing is that technology is quickly giving some people who are in the right location and have access to sufficient roof space, are perhaps ok to make a few changes to the way they use energy - to "Go off the Grid" for purely economic reasons.
Interested to hear other opinions - again just making the distinction to "Moving off the Grid" - there is a difference.
Regards
Roger