What does a solar install actually cost you to acquire?
Quick answer: divide your monthly sales and marketing spend by installs closed to get cost per install, then divide by system size in watts to get cost per watt, the number the industry actually tracks. Enter your own numbers below and compare against a per-appointment rate you enter.
Spend divided by installs. Then divided by watts.
Set your monthly spend, installs closed, and average system size to see your CAC per install and per watt. Then set a show rate and close rate to compare that against a pay-per-sit appointment model at the rate you enter.
Your Inputs
The first three sliders calculate your current CAC. The last two sliders and the price field power the appointment comparison.
Industry data puts the no-show rate at 30 to 40% even for paid leads, implying a 60 to 70% show rate. Not a guarantee.
25 to 35% is an industry-estimated band for exclusive, already-booked appointments. Not a guarantee.
Enter the rate you pay or are quoted. VA Horizon sets its rate on a short call.
Your CAC
Estimate based on the inputs you set. Not a guarantee.
Excludes any one-time setup fee. Uses the per-appointment price you enter above.
Four numbers, two comparisons.
This calculator runs two separate calculations from the same inputs: your actual CAC, and what the same install would cost through a pay-per-sit appointment model.
Cost per install
Monthly spend divided by installs closed. $20,000 spent against 4 installs is a $5,000 CAC per install.
Cost per watt
CAC divided by system size in watts. A $5,000 CAC on an 8 kW (8,000 watt) system is $0.63 per watt.
Appointments needed per install
1 divided by your show rate times your close rate, rounded up. At 65% show and 30% close, that is 1 ÷ 0.195, or about 5.1, rounded up to 6 appointments.
Booked-appointment cost per install
Appointments needed multiplied by your per-appointment price. At the default rate, 6 appointments is a $1,800 cost per install, before any one-time setup fee.
Appointments are always rounded up, never down, since a fractional appointment does not exist. A calculation that lands on 5.1 appointments still needs 6 whole appointments to be certain of covering one install.
This comparison will not always favor VA Horizon. At a low enough in-house CAC or a low enough show and close rate on the appointment side, the two numbers can land close together or even flip. Move the sliders to model your own market honestly, not a predetermined outcome.
Every default, traced to a source.
No number on this page is invented. Here is exactly where each default came from.
- CAC per watt ($0.60/W in 2025, forecast $0.84/W in 2026, a 40% spike): Wood Mackenzie, US residential solar customer acquisition costs set to spike 40% in 2026.
- No-show rate (30 to 40%, informing the 65% show-rate default): existing VA Horizon research plus industry sources via Invention Solar, how much do solar leads cost.
- Exclusive appointment close-rate band (25 to 35%): industry-estimated range, consistent with AgentZap's finding that exclusive solar leads convert meaningfully better than shared or aged leads.
- Per-appointment price (visitor-entered, default within the $200 to $500 range seen for pre-set and booked solar appointments): enter the rate you pay or are quoted. VA Horizon sets its rate on a short call.
Solar CAC, answered.
How do I calculate my solar customer acquisition cost (CAC)?
What is a normal solar CAC per watt in 2026?
How does the appointment comparison work?
Does the comparison include any one-time setup fee?
What show rate and close rate should I use if I do not know mine?
Rising CAC does not have to be your problem to solve alone.
VA Horizon books exclusive, double-confirmed solar consultation appointments. Pay per booked appointment, with pricing set on a short call. No-shows are replaced free. Book a 15-minute call to see your exact rate.
Book a CallRecommended next steps