The nearest electric box to my garage at Highline Crossing, which is about 15 meters from my garage building, and is on a different building than the one in which my garage is.

$63,000+ to achieve an off-grid/on-grid dream?

editor's blog icon

My townhome in Highline Crossing Cohousing in Littleton, Colo. I want to have solar installed on the roof and want to come as close as possible to electrifying ALL of my energy use inside it AND producing that electricity that I use locally with my solar system and possibly battery storage system as well. [Photo by Christof Demont-Heinrich]
I have a dream, a dream of being mostly off-grid and self-reliant while also remaining on the electric grid.

That dream is one step closer to becoming reality thanks to my recent successful efforts — which took eight months — to persuade my HOA, Highline Crossing Cohousing Community in Littleton, Colo., to allow individual condo owners here such as myself to pay to have individual solar installed on the shared rooftops above our attached condos at HCCC.

But is my dream of being mostly off-grid in terms of my electricity consumption while obviously also remaining tied to the grid realistic? Is it affordable (enough) for me? And, most important, from a green and environmentally friendly perspective, does my off-grid while on-grid dream make sense, environmentally?

I am going to explore each of these questions here, partly to work through, in writing, what I am going to do here at 1644 W. Canal Court in Littleton now that I can pay to have solar installed on the community owned/shared roof above my condo unit.

This so that I can begin to sort through everything and decide what I want to do. I’m going to work through it, out loud, too, because it might be helpful for others out there with the same, or similar dream, of being mostly off-grid while also being connected to the grid.

Honestly, right now, I am pretty confused about what I am going to do: I’m very unsure about, for instance, whether I am going to use my money — I only have $10,000 to put toward a solar system (+ battery) and will have to borrow the rest of the money — to focus on building as big a system as I can (here in Colorado Xcel Energy territory homeowners can now have a solar system installed that produces up to 200% of one’s annual average electricity use! The system size cap used to be just 120%!) or if I am going to go with a (much) smaller solar system so that I can add a home battery storage pack such as a Tesla Powerwall.

xcel-fair-share
An Xcel Energy solar utility meter.

On to the reflection — and consternation šŸ˜œ

Is it realistic to be (mostly) off-grid while also being on grid?
The short answer is probably no, it is not. And the main reason for this is my limited money situation — journalism professors don’t make much money: After 16 years at the University of Denver, I gross just $65,000 (I think we ALL should share our salaries, as I think keeping them secret, which social approbation dictates, favors a situation where employers pay workers less, pay them unevenly, etc.Ā  — and get away with it). If I had/made more money, I would be able to go mostly off-grid while staying on grid, most likely.

I have another concurrent goal — 100% electrification of my condo. This goal makes my dream of going off-grid while being on grid even more expensive and also more challenging. I want to eliminate my natural gas use entirely. That means converting my forced hot air gas furnace, my gas hot water heater and my gas range and oven to electric. And, doing all of that, plus adding solar and possible battery storage also involves the very likely need to upgrade my 150-amp electric panel, on which ALL circuits/breakers are already full.

Yikes!

Running some very rough numbers here:

  1. 4.5 kW – 7 kW home solar system cost = $15,000 – $25,000 (pre-Federal tax credit)
  2. Home battery storage pack cost (LG Chem RESU 10h Prime, Tesla Powerwall 2, etc.) = $10,000 – $15,000 (https://news.energysage.com/tesla-powerwall-battery-complete-review/)
  3. Electric heat pump furnace cost + installation = $4,000 – $10,000 (https://homeguide.com/costs/heat-pump-cost)
  4. Electric heat pump hot water heater cost + installation = $2,500 – $5,000 (https://www.remodelingexpense.com/costs/cost-of-heat-pump-water-heaters/)
  5. Electric panel upgrade cost = $800 – $2,500 (https://www.angi.com/articles/ask-angie-what-does-it-cost-upgrade-200-amps.htm)
  6. Running 240v capable conduit from my gas range/oven position to electric panel = $500 – $1000

In terms of a rough best-case cost scenario, to get to 100% electrified and as close as possible to my off-grid but still (barely) on-grid goal will cost roughly $33,000.

a solar EV in front of a garage with solar panels
My 2020 Chevy Bolt parked in front of the solar system that fuels it. [Photo by Christof Demont-Heinrich]
However, in reality, the lowest cost scenario would be higher: This is because I would need not a 4.5 kW home solar system, which would more than cover my current very low annual kWh total use of 3,000 kWh (my condo is NOT attached to my garage for my EV, a 2020 Chevy Bolt; that garage is a community garage and, I am proud to say, it’s electricity is supplied by a 9.3 kW solar system that I lobbied my HOA for 18 months to pay for and install), but at least a 6.5 kW to 7 kW solar system.

I would need an up to 8 kW solar system to produce enough electricity to cover the extra use that 100% electrification of my condo would require.

  1. Total average annual electricity use right now = 3,000 kWh
  2. Extra kWh needed to run an electric heat pump furnace in Colorado = 3,000+ kWh
  3. Extra kWh needed to run an electric heat pump hot water heater = 2,000 – 3,000 kWh
  4. Extra kWh needed to ran an electric range/oven = 400 – 600 kWh
  5. BEST CASE total annual extra kWh needed to cover 100% of added electric use due to 100% electrification = 8,500 kWh

I am fortunate in the fact that my roof probably could support a solar system that could produce 8,500 kWh worth of solar electricity here in sunny Colorado. But that system, of about 7 to 7.5 kW, without any battery storage, would cost me at least $23,000 (pre Federal tax credit; I am running pre tax credit numbers here because, after all, the pre-Fed Tax total is the amount that I will have to come up with to pay a solar installer).

So, now it’s time to re-do my math: I am now at $43,000 total to get perhaps somewhat near my off-grid/on-grid dream here at 1644 W. Canal Court, Littleton, Colo.

But, in fact, that best case scenario cost total really needs to be pushed higher. This is because I need to add a SECOND storage battery to get anywhere near being able to run all of my 100% electrified home off of solar electricity generated by a home solar system that is then stored, and used, locally, by me, and only me, in my condo.

My gas hot water heater. I would like to replace it with an electric heat pump water heater in the next three years or so. [Photo by Christof Demont-Heinrich]
So, let’s add another $10,000 for a second Tesla Powerwall, which would give me the ability to run about 27 kWh of electricity off of my batteries. Now, I am at $53,000 to get somewhere near achieving my off-grid/on-grid dream.

And, really, it seems likely that I would not be lucky and achieve best case cost scenarios for all of my needed elements: 100% electrification + home solar + home solar battery. So, I will add another $10,000 to account for the likelihood of less than best case cost scenarios for each element.

Now, I am at $63,000 to achieve, somewhat, my dream of being mostly off-grid while on-grid.

I cannot afford that, even if I take out a loan of $53,000. The payments would be prohibitive for me (my mortgage + HOA fees already = $1,700/month).

Environmental impact of going (mostly) off-grid while being on grid
If I COULD afford it, I WOULD put up a 7 kW solar system with two Tesla Powerwalls, upgrade my electric box and replace my gas hot water and gas furnace with electric alternatives. I’d do this regardless of whether it turned out to be cost-effective for me or not!

That’s because I see — in contrast to far too many people, ESPECIALLY Americans šŸ˜ž, most of whom are NOT taking this EMERGENCY seriously AT ALL! — that we are in a true Climate Emergency and that nothing short of radical and quick change is going to rescue us from an increasingly dire future.

I want to do as much as I can in the relatively short time I have left here on earth — I am 55 years old — to reduce as much as possible my carbon legacy. The single greatest contributions to carbon produced for most peopleĀ  = their home electricity + home heating and cooling, their transportation, and their food consumption, with beef consumption being especially problematic but other meat and dairy also adding considerably to one’s carbon footprint (I eat only white meat and a little fish and estimate that I eat about 1/5 the amount of meat the average American does).

My 2014 Nissan LEAF parked in front of the 5.5 kW rooftop solar system that powered it for a couple of years in Aurora, Colo.

I’ve done as much as I can to reduce my carbon — and general air pollution — impact by driving an all-electric car for eight years and powering that car with home solar for three of those years: Two years at my old, pre-divorce home in Aurora, Colo., onto which my now ex-wife and I installed a 5.5 kW solar system, and one year here at Highline Crossing Cohousing, where we went online with a 9.3 kW system on our shared garages in 2020.

That system now fuels my 2020 Chevy Bolt and a neighbor’s 2017 Nissan LEAF AND has produced 2,500 more kWh across its first year than we have used! We also have a 10.3 kW system on our community house here at Highline Crossing Cohousing, a system that has produced about 6,000 more kWh than we have used in that building in 2021!

Now, it’s time to attack my condo and my home heating and cooling (although, I almost never use my central AC unit here) and get rid of fossil fuels as much as possible, ideally, of course, 100%. That is the only way we are going to rescue ourselves, and, equally important, our kids and future generations from untold suffering, misery and death, misery and death which has already been affecting the world, especially poorer people in less well-off countries and places whose carbon footprint is often 1/15th or less of the average carbon footprint of the monstrously OVER-consuming American šŸ˜ž!

My own condo carbon footprint is quite a bit lower than that of most Americans with just 3,000 kWh of electricity used in my condo, which compares rather favorably to the 10,000 kWh used by the average American household. I am very conscientious of my/our energy consumption here (my two teen daughters live 50% of the time with me).

My gas forced hot air furnace at 1644 W. Canal Court. [Photo by Christof Demont-Heinrich]
Want to get rid of gas appliances
However, my condo’s direct carbon footprint isn’t reducible to electricity only: I also use natural gas, and quite a bit of it, as my furnace here in Colorado, which has a real winter — though that real winter is increasingly being reduced in length by the Climate Emergency — is a natural gas forced hot air system. I also have a gas hot water heater and a gas range/oven. Across the past 12 months, I/we have consumed 344 therms of natural gas.

I found figures that indicate that the average American household consumes somewhere between 400 and 800 therms per year. So, on this count, at 344 therms consumed across the past 12 months, I also appear to be under the average, as I am in relation to my electricity use.

BUT I do not want to be burning any fossil fuels directly! They are literally killing our future — and our present! And we need to get off of them — NOW, ASAP, IMMEDIATELY!

Which brings me back to my dream off 100% electrification + off-grid living while on the grid: Environmentally, I really, really want to achieve this dream, but, clearly, right now, financially, I cannot. That is a shame: Because it reveals that our priorities in the United States and in many places around the world are BACKWARD and just plain wrong: Getting us ALL to 100% electrification and 100% renewable energy ASAP must be a priority. But, sadly, it is not.

This leaves environmentally driven individuals such as myself in a quandary: Do we spend money that we don’t have in order to reduce our environmental and carbon impact as much as possible as quickly as possible knowing that:

a) it is costing us more than we are going to save and that we most often do not have the money to do that, which then requires borrowing money and paying interest to do the right thing;

b) because 95% (maybe 99%) of Americans are NOT doing what we are doing and are NOT going to do it, often out of financial reasons, the positive impact we will be having will be extremely negligible and possibly quite close to no positive impact at all šŸ˜–.

I would love to go to 100% electrification and to essentially off-grid living while being on-grid immediately. I cannot do that. So, what do I do?

Here are my primary choices ==>

  1. Pay for a solar system that as big as possible — 7-8 kW, and do nothing else; total estimated cost = $20,000 – $25,000. This would require borrowing about $15,000 to add to the $10,000 I have saved up right now. And I would do nothing else: I would not add a storage battery and would not convert to an electric heat pump, electric range or electric heat pump hot water heater and I would not upgrade my electric panel.
  2. Pay for a much smaller solar system — 4 kW and add a single storage battery = $20,000 – $25,000. A smaller solar system + a Tesla Powerwall because they have not had the problems that LG Chem batteries have (LG batteries have burned in Chevy Bolt’s such as mine AND they’ve had to recall home storage batteries due to fires and fire danger as well) is another option. Of course, I will produce less solar electricity, and, a single Powerwall, with its 13.5 kWh daily output capacity is not going to cover my daily use IF I electrify 100%. So, here, too, as with Option No. 1, I probably would not electrify 100%.
  3. Borrow much more money ($30,000 rather than $15,000?) and go for a 7 kW system PLUS two Tesla Powerwalls and an electrical panel upgrade, total estimated cost = $30,000 – $40,000. I’d really like to be able to do this. It would allow me to very often — though not always — be able to say that 100% of the electricity I used on a given day AND during the night was produced by the solar system on my roof.
  4. Borrow a TON of money ($50,000+) and do it ALL: Get the 7 kW solar system + two Tesla Powerwalls + upgrade my electric panel + electrify ALL of my gas appliances — furnace, hot water, range/oven, total estimated cost = $60,000+ dollars.Ā I would really LOVE to be able to do this, as I really want to get off of fossil fuels and leave DIRTY GAS in the dust, completely.
  5. Some combination of the above four options: For instance, go with a 7 kW system, build it to be battery ready, and add a battery later while doing some electrification and perhaps also an electric panel upgrade while slowly electrifying along the way, during which time I could be banking LOTS of solar generated kWh with Xcel Energy to be “used” later as electrification of my home increases my electricity use. Of course, these banked kWh won’t really have been directly generated by solar on my roof, but will be credits based on the extra kWh that I will have pushed out onto the grid across time. To me, “using” electricity banked with one’s utility is NOT as satisfying as knowing that electricity running all of my appliances and heating and cooling has been generated by solar panels on my roof.

I am a purist in this way and, frankly, I HATE fossil fuels and fossil fuel companies and the GREEDY, SHORT-SIGHTED people who run them (I have more understanding for the front-line workers in those industries because it is mostly not within their direct power to STOP the fossil fuel nightmare that we are creating; it IS within the power of the CEOs and management of these companies to STOP what they are doing!)

I know some (many?) out there might take issue with my desire to be “pure” in my solar electricity generation and use in my condo: They will say, “It’s better to push out that extra electricity and share it with your neighbors and use your money to build a bigger solar system to do more of that pushing out of solar electricity to others than to build a smaller system with a battery so that you can be more pure.” Probably true, although I doubt it could be proven one way or another what would truly be better, environmentally: Me spending money to build a bigger system that over-produces more or me spending that same money for a smaller system with a battery.

What would you do, and why, based on limited funds? Which option would you choose?

I am leaning toward borrowing quite a bit of money ($20,000 or so) to build a 6.5 kW solar system with one Tesla Powerwall and to pay for upgrading my electric panel (which, I suspect, is going to be necessary to add a battery anyway). This will almost certainly cost me more than it will save me in the long run — my current annual electric costs are only around $500 per year.

An Envi convection electric wall heater in my living room. [Photo by Christof Demont-Heinrich]
I would then add an electric heat pump water heater within two to three years and, ideally, a second Powerwall later. I think I am going to forgo the switch to an electric heat pump furnace and, instead, go with a much cheaper solution: Trying to heat my home as much as possible with Envi high efficiency convection wall heaters.

I have four of these already but have not used them since I lived in my Aurora, Colo., which has solar. I moved out of that house in Nov. 2015 after it was sold due to my divorce. I used the Envi heaters in Aurora, Colo. with our 5.5 kW solar system for five years to heat as much as possible with electricity and reduce my natural gas use substantially.

I just ordered two refurbished Envi plug-in heaters from Envi yesterday to boost our total number of heaters to six. I know that when my teen girls are not here, I can heat 100% using some of these heaters, probably no more than three at once — they draw 475 watts each. We will see if I can manage it when my kids are here, as they have a lower tolerance for wearing extra layers in the house than I do šŸ˜œ.

I think I can cover up to 80% of my winter heating, maybe more, with these all-electric heaters, thus reducing my gas heat use by 80%. Of course, the Envi wall heaters will substantially increase my kWh use, probably by 400 to 600 kWh per month from December to February and perhaps by 200 kWh per month in October, November, March and April. In total, I expect they will increase my electric use by about 2,500 – 3,000 kWh from October to April here in Littleton, Colo.

However, I estimate that my natural gas usage will drop fromĀ  about 350 therms per year to about 100 therms per year. This will represent a big efficiency gain, as in addition to a heating at least indirectly via solar gain when my solar system is installed, 250 therms is equal to 7,325 kWh, and I estimate I will be using less half of that kWh total to heat my condo with my Envi wall heaters.

When I add an electric heat pump hot water heater my gas therms used per year will drop to perhaps 30 therms, or less. And rather than converting my old gas range/oven to electric, which will be costly because the builders of my condo did NOT install a 240v outlet where the range/oven goes, I plan to buy some induction hot plates and a toaster oven and use these as much as possible.

Tesla CEO Elon Musk talking about the Tesla Powerwall.

Limitations of in-home storage batteries
Beyond cost — and probably losing money long-term due to my laser focus on eliminating fossil fuel use as much as possible in my condo — the biggest hurdles I will face in my attempt to realize, as much as possible, an off-grid but also (as little as possible) on-grid existence, would be the limitations of storage batteries such as the Powerwall.

My biggest electric draw is my electric dryer: I would plan ALWAYS to do my laundry and use my electric dryer during midday on sunny days here in Colorado. However, the Envi heaters are going to be drawing up to 40 kWh of electricity a day, with much of that draw occurring at night. Obviously, the 13.5 kWh a Powerwall can provide isn’t going to cover that. Even two Powerwalls would not be able to cover 40 kWh a day, although I/we have to take into account that probably 20 kWh of the draw by my Envi heaters would occur during sun hours.

My daughter Kyra and me in front of my 2020 Chevy Bolt before our departure in Goleta, Calif. on Friday, Aug. 27, 2021. [Photo by Amanda Heinrich]
And, of course, when I convert my natural gas hot water heater (which is reaching the end of its life anyway) in two to three years, the electric heat pump hot water heater will also be drawing lots of kWh. Add that in to Envi wall heater draw during the winter, which is also the time of year when I would see the shortest, and also highest number of gray days here in the Denver area, and even with a 6.5 kW system and two Powerwalls, and me only running my dryer during a sunny day at peak sun in December, I would still not be able to run everything without sometimes substantially drawing from the grid.

HOWEVER, from early April to early October, I would very often — maybe close to always — be able to run 100% of my electric from my solar and from a single Powerwall, even with an electric heat pump hot water heater. With two Powerwalls, I might be able to go from March 15 to Nov. 15 every year and be running nearly 100% on electricity generated by my solar system and used, on the spot, during the day, and then meted out at night by the Powerwalls. And, with two Powerwalls, from Nov. 15 – March 15, I probably could say that 50%, or more, of the electricity I was using was generated by my rooftop system AND I would be overproducing electricity for six months of the year, too, with a 6 kW + 1 Powerwall set-up, I think.



In short, even with just one Powerwall and a 6 kW system and using my Envi convection wall heaters and an electric heat pump water heater I would be running almost exclusively on my own locally generated electricity for at least six and up to eight months per year, with the other four months seeing comparatively little grid draw compared to all of my non-solar and non-electrified and non Powerwall neighbors. That would be quite an achievement. But, of course, an expensive one, too.

I do think that because I love to talk solar, energy, electricity and environment and because I love numbers — I really like using the Emporia Energy App to watch our HCCC solar systems production vs. our garages and community center electric consumption and our AP Systems solar monitoring App that I would truly enjoy having a battery and watching, and knowing more about, where the electricity I am using is coming from.

Having one, and maybe eventually two, Powerwalls would also encourage even further electricity conservation on my part.

So, in sum, I am leaning toward going for around a 6 kW system at about $20,000 before the Federal Tax Credit plus a Powerwall, which will add another $12,000 to the system, for a $32,000 total, a set-up which would cost about $25,000 after the Federal Tax Credit. That means I will need to borrow $22,000, though I should be able to pay that down by about $10,000 more this summer if my summer online courses fill (they did not last summer).

Hmm….that is feeling rather above my capacity.

So, I may have to resize the system down to a 5 kW system, which would bring my total down to about $20,000 post tax credit.

This 9.4 kW rooftop solar system on the garage rooftops at Highline Crossing Cohousing in Littleton, Colo. fuels multiple electric vehicles. [Photo by Silky Shots Photography, 2020]
Or, maybe I should just go with a battery ready 6 kW system and only have to borrow $10,000. I don’t know. And, obviously, I cannot makeup my mind.

I do wish that we had a system of direct infusion of money extracted from the fossil fuel companies who have destroyed, and continue to destroy our past, present and future which would see that money would DIRECTLY subsidize millions of projects just like mine where homeowners go solar and and electrify and get off of fossil fuels 100%.

We are in a true EMERGENCY and need to ACT now (actually, we should have already acted) to get off of fossil fuels 100%. And if a deeply driven and committed activist such as me is having difficulty making a decision to invest money (I don’t have) into rescuing the climate and our earth and the future of living beings on earth, that is a sign that we are not in a very good place at all and, in fact, are in deep, deep trouble indeed. šŸ˜–

Young people were a big presence at the Climate Strike in September 2020.