2021-088 Solar Program UpdateDate: 10/15/2021 Report No. 2021-088
INFORMAL STAFF REPORT
TO MAYOR AND CITY COUNCIL
SUBJECT:
Update on the City’s Solar Rebate Program funds.
BACKGROUND:
The City of Denton implemented the Solar Rebate Program in 2009 to help offset initial equipment
costs related to solar installations. Since that time, solar prices have decreased 35%, leading to an
increase in solar installations, system sizes, and rebate amounts per project.
On October 1, 2020 the City of Denton's Solar Rebate Program started with a budget of $500,000
for solar installations. During FY2021, the City received 104 solar applications that qualified for
$500,000 in rebates.
DISCUSSION:
The rapid disbursement of solar rebate funds is driven by the continued drop in solar installation
costs which has led to an increase in installations and system sizes. To put into perspective, for
FY2019, the $500,000 designated to the Solar Rebate Program lasted until June of 2019 (8
months). For the FY2020, $500,000 in rebate funds lasted until February of 2020 (3 months). For
FY2021, solar rebate funds lasted until early December of 2020 (2 months).
It is also worth noting that customers are choosing to install solar systems without receiving a
rebate. If we compare FY2019 and FY2020 we see that while the total number of solar installations
increased by 56 from 132 to 188, installations that received a rebate actually decreased from 116
to 108 but solar installations that did not receive a rebate increased 400% from 16 to 80. This trend
is expected to continue.
Another factor contributing to the quick allocation of solar rebates is the size of the systems. Low
solar installation costs have allowed customers to purchase more solar equipment, which has led
to higher rebate amounts since rebates are based on the system's size. For example, the average
system size for FY2019, FY2020, and FY2021 are 7.27AC kW, 7.60AC kW, and 8.61AC kW,
respectively.
The structure of the rebate was modified several times along the way to address continued drop in
system prices and to allow dollars to go further. When the program started it was a flat $3 per AC
Watt up to $15,000. In 2014 it was changed to $1.50 per Watt up to $30,000. In 2018 it went to
$0.75 per watt for solar only and $1.50 per watt when coupled with batteries. The last change
came about in October of 2019. That current structure is shown below.
PV Only PV with Battery Storage
3.0 kW to 5.0 kW $0.80 per AC Watt 3.0 kW to 5.0 kW $1.20 per AC Watt
5.1 kW to 10.0 kW $0.60 per AC Watt 5.1 kW to 10.0 kW $0.90 per AC Watt
Above 10.1 kW $0.40 per AC Watt Above 10.1 kW $0.60 per AC Watt
Date: 10/15/2021 Report No. 2021-088
It only took two months to commit the solar rebate funds entirely in the FY2021, and we exceeded
last year’s record installation numbers for systems that did not receive a rebate.
For FY2022 we are once again offering rebates for Residential and Commercial PV systems. The
Authorized amount budgeted is $500,000 and we have no doubt the trends we’ve seen to date will
continue as system applications have already begun to come in.
Below are a table and graphs showing the budgeted rebate amounts, total rebates given, total
number of solar installations, and average system sizes per fiscal year since 2017.
Table A
Solar Installation and Rebates per Fiscal Year
Fiscal Year 2017 2018 2019 2020 2021
Rebate
Budget $200,000 $300,000 $500,000 $500,000 $500,000
Rebates
Given 32 55 116 108 104
Installs w/o
Rebates 13 27 16 80 101
Systems
Installed 45 82 132 188 205
Avg. System
Size ACkW
27.21 All*
7.36 Res.
Only
11.65 All*
6.25 Res.
only
7.27 All*
7.25 Res.
only
7.60 All*
7.16 Res.
only
8.61 All*
7.83 Res.
only
*2017: all installed includes Target (660 ACkW) and Embassy Suites (248 ACkW)
*2018: all installed includes Tetra Pak (420 ACkW) and All About Imports (36.38 ACkW)
*2019: all installed includes two small commercial (5.04 and 11.40 ACkW)
*2020: all installed incudes Community Pharmacy (80 ACkW) and a small commercial system (4.93 ACkW)
*2021: all installed includes Denton ISD Wilson Elementary (169 ACkW)
Date: 10/15/2021 Report No. 2021-088
Graph A
STAFF CONTACT:
Bill Shepherd
(940) 349-7493
William.Shepherd@cityofdenton.com
STAFF TIME TO COMPLETE: Juan Pagoada-Reyes – 1.0 Hours