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---
slug: solar-one-year
title: "Solar: One Year"
date: "2023-12-29T08:06:45-04:00"
pics:
dashboard:
css: "image"
tip: "Total 2023 energy production and consumption."
sources:
- "/files/posts/solar-one-year/dashboard.webp"
- src: "/files/posts/solar-one-year/dashboard.png"
width: 855
height: 527
bill:
css: "image"
tip: "Our July power bill with monthly usage and amount due highlighted."
sources:
- "/files/posts/solar-one-year/bill-20230722.webp"
- src: "/files/posts/solar-one-year/bill-20230722.png"
width: 873
height: 534
tables:
savings:
# table columns (required)
cols:
- id: "desc"
name: "Description"
tip: "Description"
- id: "amount"
name: "Amount ($)"
tip: "Amount of money saved, in dollars."
align: "right"
# table rows (required)
rows:
- amount: "$868.00"
desc: "Energy Produced (6.2 [MWh](https://en.wikipedia.org/wiki/Kilowatt-hour#Multiples \"megawatt-hour (MWh)\"), $0.14/[kWh](https://en.wikipedia.org/wiki/Kilowatt-hour \"kilowatt-hour (kWh)\"))"
- amount: "$260.25"
desc: "[Fairfax County Solar Energy Equipment Tax Exemption](https://www.fairfaxcounty.gov/taxes/relief/real-estate-solar-equipment \"Fairfax County Solar Energy Equipment Tax Exemption\")"
- amount: "$179.52"
desc: "[SRECs](https://en.wikipedia.org/wiki/Solar_Renewable_Energy_Certificate \"Solar Renewable Energy Credit (SREC)\")"
- amount: "**$1307.77**"
desc: "**Total**"
---
{{< pe-figure "dashboard" >}}
Last year we got [rooftop solar][solar]. The picture above is our
[Enphase][] dashboard, which shows how the solar panels performed in
2023.
The blue bars indicate the energy produced by our solar panels and the
orange bars indicate the energy consumed by our house, in
[megawatt-hours (MWh)][MWh].
The relevant values are:
* Consumed: Total energy consumed by our house.
* Produced: Total energy generated by our solar panels.
* Net Imported: Energy we are actually billed for.
Any excess energy that we produce is exported back to the grid and
credited to our account ([net metering][]), so our power bills during
the spring and early summer look like this:
{{< pe-figure "bill" >}}
The sections of the bill highlighted in red show the following,
respectively:
1. Four months of zero net energy use.
2. A bare minimum power bill.
## Savings
Here's a breakdown of the money we saved this year from solar:
{{< table "savings" >}}
Notes:
* The solar panels offset **62%** of our energy use for the year
(6.2/9.9 = ~0.62) and saved us **$868.00** (6200 kWh * $0.14/[kWh][] =
$868).
* We received a **$260.25** property tax exemption from the [Fairfax
County Solar Energy Equipment Tax Exemption][tax-exemption].
* We generated 6 [solar renewable energy credits (SRECs)][srec] in 2023
and 5 have been sold. We received **$179.52** for them (after fees).
The expected lifetime of the solar panels is 20 years. We expect to
recoup the initial installation cost in 11-13 years.
That's longer than usual (most folks try to break even in 5-8 years),
but we're okay with it; our house is partially shaded and our panel
placement is deliberately less than optimal for aesthetic reasons.
[solar]: {{< relref "posts/2022-09-11-solar-panels.md" >}}
"Solar Panels installed on our roof."
[enphase]: https://enphaseenergy.com/
"Enphase"
[kwh]: https://en.wikipedia.org/wiki/Kilowatt-hour
"kilowatt-hour (kWh)"
[mwh]: https://en.wikipedia.org/wiki/Kilowatt-hour#Multiples
"megawatt-hour (MWh)"
[net metering]: https://en.wikipedia.org/wiki/Net_metering
"Net metering"
[srec]: https://en.wikipedia.org/wiki/Solar_Renewable_Energy_Certificate
"Solar Renewable Energy Credit (SREC)"
[tax-exemption]: https://www.fairfaxcounty.gov/taxes/relief/real-estate-solar-equipment
"Solar Energy Equipment Tax Exemption for Fairfax County"
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