A lot of people have been asking us about our new solar panels. Everything from how they work, how much power do they produce, how much did it cost, how much will it save, and why did we do it.
This will be a long post, but I hope to provide insight with data as to our decisions and thoughts. I will be as transparent as possible. I tried to split my thoughts into categories that would be easy to follow and tell the story.
- Why we went Solar
- System Cost
- Loan process
- Expected Saves
- Monthly usage before
- Expected usage afterward
- System Layout and size
- Installation Process
- Related Posts
- Nest thermostats (different post)
- Nissan Leaf
Why the Murphy’s Went Solar
As someone who got a degree in Environmental Sustainability in Green Business, the longevity of our planet has always been something that is important to me. Everything I do, take the theory of, if everyone did this action, how would it multiple? Does this action create a positive chain reaction, or not? There are many reasons we decided to go solar, and diving through all of them will be a bore, but to name a few:
- Setting an example for my two Kids
- Being less dependent on a limited fuel source (oil or natural gas)
- Investing in a growing industry that is fighting my cause to lower CO2 emissions
- Be an early adopter in a technology that everyone will use one day (I truly believe that)
- Show others who are on the fence a realistic example that it can be done (neighbors, family, and friends)
- This is the first house I own
- Our house is heated by an electric system (most are gas)
- Wanted to run the A/C more and not feel the A/C stabbing me every month.
I am sure there are more, but you get the point. Now to back up my wants with research and numbers.
About our House
We have named our House Manitou Manor, as all good places need a name. We bought the house in October of 2015. We have lived here for two winters, however, last summer we spent abroad so our summer usage from last year is a bit miss leading. The house sat at 82 degrees from June to mid August. Everything in the house is electric. To the point were we don’t even have a gas line run onto our lot. Its a gorgeous home built in 2010, and roughly 2900 soft. Insulation is decent, HVAC system is relatively new, appliances standard, and drive a fully electric Nissan Leaf (more on this in another post).
We are currently with CoServ as an electric provider. We are in an area of Texas that can not choose its provider. This is not true for most of the state but is what it is for parts of Plano, McKinney, Frisco and Prosper. This plays an important role because CoServ does not currently offer a buy-back package. Meaning if we produce more electricity than we use, CoServ will not pay us for producing that electricity. This means, that we only wanted a system large enough to cover our usage on low days (spring and fall) but would only lower our grid usage during hot summer days, and cold winter days.
We had to find a balance of produce as much as we can but don’t produce so much that we aren’t full advantage of the electricity we are making.
This conversation completely changes if you have an electric provider that does payback for over production. Keep this in mind as you continue reading as it directly impacts the size of the system we ended up with and the final price.
Our CoServ plan is currently set to the Wind Power plan, with a pre-purchase position of solar from CoServ’s new solar plant just north of Denton, Texas.
Previously our Electric Bill was easily $200+ in the summer, and about the same in the winter. Here is a graph that shows you our usage in KWH.
You can see the kWh in the image above show our total monthly usage. When we are home and running the HVAC, our usage can easily go over 2,000 kWh in a month. However, at minimum (when we are home) we use about 1,000 kWh.
Then if you go to a daily view:
You will see 50 kWh day is normal during heating or cooling periods, while it tops off around 100 kWhs and peaks around 150 kWhs. On this grid, you also have 4 markers. They mark specific events that will make a difference to our electric bill.
A: When we left our trip abroad.
B: When we returned
C: When I bought home my Nissan Leaf
D: When the panels were installed
If you look at usage after the panels were installed you will see only the power we consumed from the grid. While this is not technically accurate, you can think of it as the house will pull power from the panels first, then pull from the grid. So if the panels are producing enough power to fulfill our needs, we will pull no power from the grid. However, at night when there is no sun we will pull from the grid.
Working with our solar provider, Petersen Dean, we calculated that an 8.40 KW system would be the right size for us based on usage and our provider CoServ. This size system will produce 10,418 kWh a year. Some months will be higher due to longer summer days, some days will have a lower production to rain, clouds, etc, but that is the expected annual production.
PetersenDean created the chart below for us analyzing sunny days, during each month and the expected production of each month. Then compared it to our year’s previous usage.
We had to estimate what our summer usage would be if we didn’t travel during that time.
But as you can see the winter will have less production than in the summer due to longer summer days, and more direct sunlight due to earth’s tilt.
So answer the question directly, how much will you save, I don’t know. It is too early to tell. However, the math supports that we should pay around $100 in the summer and winter during high demand time. Then during spring and fall, we should pay little to nothing.
While all the saving from the grid is nice, we still had to pay for the panels, installation, system monitoring, the whole 9-yards. I will use rounded numbers here, to make the math a bit similar, but you will get the idea.
The system overall cost about $25,000. Then Uncle Sam kits back 30%, and CoServ also kicks back some money to support the cause.
|-$5,769.23||Tax Incentive (30%)|
|$16,605.77||Out of Pocket Cost|
Now to figure how long it would take us to pay $16,605 if we were paying for electricity into the grid. This calculation is a guess at best. From the performance of the system, weather during each season from a sunlight level and temperature standpoint, there are a lot of things that can swing the numbers. As I reviewed earlier, we expect 50% of our usage during the peak summer and winter too by self-powered, and almost all usage during spring and fall.
This meaning a bill averaging a savings of $150+ in summer and winter, and less than $10 in the fall and spring. Being in north Texas that means months June through September are heavy A/C months and for us January and February are cold. I like the table below to show my thought process.
|Month||Savings on Bill|
That is not a ton of savings, but will pay its self off in 10 years.
I want to point out. This is still all speculation to a point. Once we have a few more months under our belts, we will have must more data to work with and estimate with. A ten-year payout would be a decent expected payout of current technology in Solar. Most estimates are 7 to 11 years.
The install process was fairly straightforward. Unfortunately, I didnt get the best pictures but I did get a few to show the process.
- Install mounting to roof
- Install micro-inverters and daisy chain wires together
- Install solar panels on roof
- Wire into breaker
- Wire breaker into main panel
To quickly define the difference: Usage is how many electricity we are consuming by running the HVAC system, running our computers, TVs, iPads, refrigerator, etc. Production is how much electricity we are creating.
Surprisingly, it is very challenging to capture both accurately. CoServ offers a great online portal with their new smart meters that breaks down usage to a 15 min interval. It is great and you can see when the dryer is running when the A/C turns on, and anytime there is a big pull on the power in your home.
Here is an example of what CoServ looks like with meter spinning backward on days we produced more than we used.
We got hooked up with MyEnlighten powered by an Envoy system to track Production. This system also seems to well. It is hard to see how accurate it is, but the data you can see out of it seems very comprehensive.
Here is a screenshot from MyEnlighten showing a few examples of the data we receive from the unit. It can be grouped into months, days, or hourly views. They also send monthly emails to keep you in the loop.
The reason conception gets hard to track is because we will use the electricity we produce before we use electricity from the grid. This means the CoServ meter could be spinning backward while we are still using electricity. But that means the house is producing more electricity than it is using. This is a good thing, but the backward and forward spinning of the meter means pulling all the information of how much was pulled from the grid at the end of the day, and how much was produced tells will get you full consumption.
Overall, this is a big expensive science project. We know its a risk and a gamble that we will recoup the money it cost to install, however, we know at some point this will happen. It is just a matter of when. For myself, I couldn’t be more excited. I feel great every time I pull up to my house knowing that I am producing most of my own electrical needs and not continuing to wait for someone else to solve the world’s problems. I think it is setting an amazing example to my children and showing them the importance of the how to love the earth and the place we call home.
I will continue to post more about our journey as we learn more. I hope to soon write a post about the Nissan leaf we purchased and the Nest thermostats. I want to review the why/how these changes are important and why we made those decisions.
Till next time,