Solar in Connecticut – A Year in Review

It has been a while since I have posted on my solar install, but I wanted to wait until the year was over to be able to give a full accounting. Any posts earlier woudl not reallyhave added much new information.

First things first – what does my system look like, this is what was installed (from the Tesla documentation):

  • Quantity: 24 Panels
  • System Size: 7.56 kW
  • Est. Annual Production: 6959 kWh
  • One Powerwall
  • Location: Newtown in Connecticut – I have a house, the panels are installed on the roof of the house

2020 Production and Usage:

My solar Production and Home utilization for 2020


  • Solar energy Produced (kWh) 7053
  • Home usage ( kWh): 8664

So, the estimate that Tesla gave me in the beginning of the project was very close – production is determined by so many factors that can’t really all be taken into consideration but I am heartened to see that I am pretty much right where I hoped to be.

The sizing of the system was done to be able to cover most of my energy needs over the year – you can see I overproduce in the May/June and Aug/Sep which helps – more on that below:

Note: there is a branch or two on a tree that will be going down to get some more late day hours of production for next year …

Impact on Electricity Bill:

Just keep one thing in mind – the period for my electricity bill and the monthly stats for Tesla do not align – Eversource bills from the 23rd of each month to the 22nd of the next and the Tesla stats I created are based on a full monthly period (1st – 28th/30th/31st).

2019 Bills2020 BillsSavings
Compare 2019 to 2020 Eversource Bills

This table only shows part of the story though – what I really need to compare was what I would have payed Eversource for the electricity that my house used vs what I actually had to pay Eversource for. That is really what shows me the savings for 2020 energy that I did not have to buy from Eversource:

From Grid (kWh)To Grid (kWh)Grid ResultskWh SavedEversource Sav
543.1025.80517.30306.500 $65.49
489.70266.60223.10414.500 $88.56
503.00441.8061.20634.000 $135.46
474.60404.7069.90635.900 $135.87
378.50633.60-255.10912.500 $194.96
296.50424.10-127.60865.800 $184.99
475.30378.8096.50794.200 $194.32
373.80354.5019.30702.900 $171.99
286.40304.70-18.30641.000 $156.84
381.20158.90222.30414.800 $ 101.49
487.30119.80367.50322.300 $78.86
741.9028.80713.10200.600 $ 49.08

The numbers above make some assumptions in terms of rates and also that I am counting a surplus production (= I exported more to the grid than I consumed) as a saving. Overall I would have had to pay $1557 more for electricity if I did not have solar production. That is significant in terms of saving.

Connected Solutions

If you have read my posting about joining the Connected Solutions program you will know that it is a bit opaque in terms of what your actual earnings can be. Basically it allows the electricity supplier to tap your Powerwall when it needs energy during high usage times and you get paid for that in the end of the year.

So, the results were actually quite encouraging – Eversource tapped my battery 30 times over the summer and in December Tesla sent me a check for $451. Tesla coordinates the program for all of it’s deployed batteries and takes some money off the top of what Eversource pays out – but that is a known issue from the start. The only thing I don’t like about this program is that there is no place in either your Tesla app or the Tesla portal that gives an update of the details – you have no way to verify how many events happen, how much energy was actually taken and see how the program progresses over the year- all you get is a an email that a check was sent and letter with the check that tells you what it is for – that is it.

Since Tesla is obviously crunching numbers to send you money at the end of the year, I can’t see that it would be that hard to add that information to the the app or the portal on the web – I really dislike black holes when it comes to programs like this. Tesla – are you listening? 🙂 Give me data!

Final Financials:

Keep in mind – the periods for billing & payment do not match the strict monthly stats by Tesla so the numbers do not add up 100%. The difference is not so large that it would have made me change my calculations to match the billing cycle … that just seemed too much detail for no real gain.

Estimated 2020 Electic Bill $ 1,866.00
Actual Eversource Bills $    425.20
Solar Array Rent $ 1,000.00
Total Savings 2020: $    440.80
Electric Production and Solar Array Savings

This is just for the electricity production – I saved more than $440 last year and once electricity rates go up again (as they will eventually) I assume I will have higher savings.

I do not include the costs for the Powerwall in this equation since it is not related to electric production but is rather a back-up system only. Also, I overpay my monthly payments (I financed the battery) so I can pay it off earlier and that would further throw off the picture.

The Powerwall did come in handy during the August 2020 storm that left us without grid power for a week – I had more than 190hrs of backup time and we were never actually out of power during that time since we had solar and the battery and the weather during the grid outage was sunny and we never really had a problem – I also still have my backup generator that I keep as the backup to the backup for times when solar production might be low or non-existent. Keep in mind – unless you have a battery, in times of a grid outage your solar array will shut down and be unavailable. By law, a solar array can only run when there is an active grid connection – unless the system includes a battery.

What do I like what do I not like?

The technology is good – you set it and forget it, it just works. I only had one event in the summer during the power outage where I had to physically shut down my solar charger as it was not charging the battery. That was the one and only time and it took my only 5 minutes to take care of it.

The one thing I am not enamored with is the communications black hole that is Tesla as a company and how slow things are overall. The order in 2019 eventually went through but it was slooooooow. Just as I was about to cancel it I received the notification that Tesla was ready to schedule an install date.

Last year in August I ordered a second Powerwall … an order I eventually cancelled in mid December as there was absolutely no movement on it (no matter how many calls I had) and I personally don’t like having to run after companies asking them to please take my money.

From what I gather, demand in California is sucking up all the oxygen in the system and New England is the unloved, redheaded stepchild. People I know did get their full systems ordered and installed during that same period in this area which left me to conclude that Tesla probably really likes new installs as those look great on paper, but existing customers don’t make the company shine in the eyes of stock analysts so we don’t get much love – at this point in time. I think that basically the demand is so large that Tesla is picking and choosing where to use their capacity where it makes most sense for their business and an order of a second Powerwall in Connecticut just does not feature high on the list of things to get done. Hopefully that will change over time but for that to actually then translate into a more stable business long term, Tesla will really have to put allot of work into customer service and communications. Currently those two things are so poor that I have a hard time suggesting Tesla to anyone at this time – no matter how much less expensive they have priced themselves compared to the competition. This will hopefully change in the future – good customer service is what makes companies have longevity and – pun intended – it is not rocket science.

Backup is all good

Solar Update – It’s actually all great news!

The summer is hot, and electricity rates in CT are goin up – I just read this articles in the Hartford Courant.

Obviously, one of the reasons I had been looking into Solar for the last few years was the fact that prices ALWAYS rise over time. Now having Solar I look at my Eversource elctricity bill and it tells me things like this:

The last three electricity bills I had were $9.62 each – just the base connection fee. Even while I am using allot more electricity now with air conditioning (it is HOT and HUMID)I am not worried as I still have enough carry forward to easily make it through August. Once September arrives air conditioning will decline significantly so I will end up not paying any electricity bill though the end of the year – hopefully! My solar array actually still creates more electricity per day than the house uses, more about that just below

ConnectedSolutions Kicked In

What the excerpt from my electricity bill above does not show is the fact that I am now participating in ConenctedSolutions and my Powerwall is exporting electricity to the grid just about every day – usually exactly 9.4 kWh starting at 4 PM – leaving it 20% capacity by the end of the day. The income for that will be distributed by the end of the year – I am looking forward to see how much that will end up being!

Whole-House Backup is a Great thing!

The other thing I am grateful for is the fact that my Powerwall has saved our bacon a few times by keeping the house running while the whole neighborhood was out of power:

The smaller 5 minutes outages were just nuisances – but the July 7th was big – a car accident had taken out a pole on our road and because our house had backup I had no issue leaving in the morning knowing that the house will run for a good 10 hours on the battery.

My conclusions so Far

Solar energy totally works – and it really saves money – you should get solar as soon as possible.

If you can afford it – buy/finance your system – then you get all the tax incentives and the TCO is the lowest.

If you can’t afford to purchase/finance – rent from Tesla. – I put $100.00 down when I went online to order it and pay $100/month for a medium sized array that totally meets my needs.

Battery Back-up is a bit more difficult to make a recommendation on – I got it on the premise of using it as a BACKUP, I did not know about ConenctedSolutions at that time – but as I am still eligible for the federal tax incentive for the battery AND I will be making money off of it I am expecting that I might be able to have the battery pay for itself and pay down the loan for it much earlier.

If you want to take a closer look at any of Tesla’s products then please use my referral link, both of us will get some benefits depending on the products you choose to go with.

Solar in CT – Can I Now Make Money Using My Powerwall?

Thought I’d share this right away – I just received this email below a few minutes ago from Tesla. This is the kind of stuff I had been waiting for – the next generation of the modern grid here distributed battery storage is tied together into a large virtual unit and used to aid the grid in time of surging electricity need. Whereas this is not a totally new program for Tesla, apparently it is new in the northeast – or at least I had not heard that it was available for my utility until now.

Vehicle-to-Grid is a technology that is already in use in some countries (Japan being the first one to come to mind) and tying in home battery solutions just makes sense.

This is obviously a program by Tesla where they play the role of the virtual power supplier towards the local electric utility. Tesla does have experience in these things on a large scale and they have access and control to all of the devices they have deployed anyway. standard devices, standard software and standard installation – makes for a great oportunity.

Here is a link to their FAQ they sent. To me this sounds really interesting – the possibility of this is one of the (granted minor) reasons why I chose Tesla and wanted a Powerwall to begin with. The ability to earn extra cash will be interesting – though I will have to review what an analysis of the numbers tell me – how does this compare to me being able to “bank” overproduction of electricity with my utility and reduce my overall power bill that way? And, my utility also pays out any net-gains of my overproduction to me in cash at the end of Summer. I will have to analyze that and see which solution makes more sense for me once I start seeing numbers from Tesla. Frankly, their FAQ is not really detailed when it comes to the nitty-gritty in terms of what kind of $ per kWh they are talking about. It is is lower than what I pay to and get reimbursed for by my utility it might not be worth it to me. Any electricity that was sent via this program to the grid/I need to charge up my battery is electricity that I am not “banking”. Well, the numbers will show me.

Overall – a positive way forward for the grid and solar power/battery owners in New England in my mind!

Rental Tesla Solar in Connecticut – The First Month

OK, so my first month of solar power with a rented Tesla system and a Tesla Powerwall is in the books and I have my first preliminary thoughts on the system and the first month in numbers.

System overall:

Let’s look for that famous three word answer – in my case it would be [reliable] – [no touch] – [efficient]. The install was clean and fast, the system works and unless I have some snow to remove from the panels there is nothing for me to do. Other than snow clearing (I have one of those long snow doohickeys) I do expect to need to wash the panels a few times a year to get rid of dust and pollen that can actually impact solar production significantly, but that is it.

Solar Production and My Initial Usage

Tesla really designs their systems to be set-it-and-forget-it. I do like looking at the phone app and see what the production looks like, just so I can see how the current weather situation and cloud cover translate into solar production. At this time of the year I can expect some production to start around 8 AM and end somewhere around 4:00 – 4:30 PM. The most I produced on a single day so far was 18.4 kWh and the least was 0.9 kWh. My house’s average daily energy usage is somewhere in the 26 – 28 kWh range, depending on how many Christmas ornaments we had running … 😉

Economics – The first Month

As for Connecticut January is pretty much the darkest part of winter, I am looking at this month to be my low end of what I can expect in energy production. I also just received my first electric bill, so now I have actual numbers to put against what my estimates were and I have some conclusions that I can now support with those numbers. In my data below I am only looking at the dates Jan 01-24 as that corresponds with the dates on my electric bill (Eversource here in CT) and the period where I actually had Solar running – here we go:

  • Jan 2019 billed to me: 884 kWh
  • Jan 2020 billed to me: 638 kWh (= -27%)

This includes the days of the billing period prior to turning Solar on so numbers are a bit skewered.

For the actual Jan 02-24 period the numbers are:

  • Home energy usage total: 596 kWh
  • Purchased from grid: 401 kWh
  • Exported to grid: 14 kWh
  • energy saved/created by solar: 209 kWh

So – What does this mean and what are my conclusions?

In Connecticut we do not have time-of-service rates, the generation rate for electricity is the same no matter what time of the day you use it from the grid. Your bill will have a generation portion and then a delivery charge that is made up of several fees that are tied to the amount of kWh you used (i.e. 5009 kWh x $0.0167 … etc.). If I take the 209 kWh that I saved last month that would have amounted to an additional $44.70 on my electric bill. Actually not bad for January.

The Economics

Next, what about the pure economics of the system? One month in the dead of winter can’t really tell you what a whole year will look like, but it does give me enough to guestimate:

I used 8730 kWh of energy in 2019, costing me about $1870.00 for the year. My Solar rent will cost me approx $1200.00/year (plus taxes, not sure of those yet) so if I am able to produce ~30% of the electricity I use for the year I will come out at even – the savings will be enough to cover the rental fees and judging by January I am confident that will not be a problem. Anything more than 30% will give me money back into my pocket. If I somehow manage to produce enough electricity over the year to zero out my grid usage I will be able to make the maximum of ~$600.00 profit if my energy usage stays the same in 2020 as it was in 2019. Frankly, I have my doubts that is possible with the medium size system that I have on the house, but I do think I can make significant savings and be left with less money out of pocket for my electricity needs.

What is the Case for a Battery?

When it comes to the Tesla Powerwall things are different. Connecticut has net metering without time-of-use rates – what happens here is that a customer is billed for the net amount of kWh used.

So if I use 100 kWh from the grid in a month and sell 20 kWh or overproduction back to the grid I end up paying for 80 kWh of energy. If I export more back to the grid than I use, I create a credit of kWh that rolls over to the next month. Because of this model, there is no economic value in storing excess power production in a battery to use it later – there is no scenario in which I can save money – In effect the grid turns into my battery.

There is a case to be made for a larger solar system to produce more energy overall (especially if I ever get an electric car … I WANT ONE!), but from a pure economic point the Powerwall does not add any saving, it just ends up costing money.

It’s All About the Back-up For Me

This is where I add the “BUT” to the discussion – I did not get the Powerwall for it’s economic value (I already knew I would not be able to save more money), I got the battery to avoid outages and be more energy independent.

I live in the suburbs and do have to deal with power outages now and then. Having a battery back-up that kicks in automatically when grid power fails has value to me. I had 3 outages last year ranging from 1 hour to 6 – two of them were caused by accidents that took out power poles, one was a bad storm where some trees came down and impacted the grid. And .. let’s not think back to Superstorm Sandy a few years back – 6 days of outage.

By law, grid tie systems without a battery backup are required to shut down during a grid outage – no grid power also means no solar power. That is why I went for a Powerwall – I will still have power during a power outage and be also have the immediate back-up that takes over in a few seconds in form of the battery and be able to generate solar power for my daily usage.

Because of this, I also have set my Powerwall to run in “Backup-Only” mode as there is no financial benefit to saving excess power in the battery for later use – I simply reserve all of it’s capacity for a possible outage. My testing shows me that I can expect about 9 – 10 hours of power for my house – longer if I start shutting down things that use electricity. I think I can stretch it to 20 hours if I need to, especially if I turn on my generator to run the critical load circuits as those tend to be big consumers of electricity.

Future Plans

Future plans – there are MANY of those! The main thing I want to look into is possibly switching my hot water generation from oil to electricity. The current hot water system is getting old and will need an upgrade/replacement over the next few years and depending on my electricity production I think I will move it from oil to electricity – probably a hybrid electric one. I will need to wait for another 4 – 6 months so I can see what my real world long term production is so I can make a better determination if that is the right thing to do. Depending on the numbers, it might require an upgrade of my medium sized solar system to a large size system – or if it might not make any sense at all. That is one of the reasons I went with Tesla rental – upping the size of an existing system does not cost any additional money – they come, install the the upgrade and then just bill for the increase in rent. For me that means I’d go from $100/month to $150/month. I will have plenty of opportunity to crunch numbers on that (that is a guilty pleasure of mine …) and I will not know until at least June/July if the savings in fuel oil and the electricity I can expect to use make financial sense overall at all.

I have pother plans in the works along this line, and will share them over time as they come to fruit – some of them will be quite interesting methinks!