Built on open data and published models
PVGIS
NASA POWER
NOAA
pvlib
A full year of your roof, calculated
SolarSolution Studio runs every hour of a typical year at your address — sun, shade, heat and your own tariff — and shows the answer in numbers you can check.
Figures for the 7.2 kW San Jose example below, calculated in SolarSolution Studio on a PVGIS typical weather year. CO₂ at California’s grid average of about 0.22 kg per kWh (EPA). Your own roof gives your own numbers.
Five steps from roof to report
Where the shadows fall, what the equipment can pass, what the roof makes and when it pays for itself — then all of it in one report you can hand to an installer.
3D layout
Place the house and its roof, then the panels, trees and neighbors. Drag the sun through any hour of any day and watch the shadows move — the sun you see is the sun the numbers count.
You set
House, roof, arrays, trees
You get
Live shadows at any hour
Model
NOAA sun position
Example
7.2 kW
18 panels on a 40° roof
Equipment & wiring
Pick modules and inverters from a library of US residential models from NREL’s SAM database, or enter your own from the datasheet. Wire each array to an inverter input and watch DC and AC capacity and the DC/AC ratio follow.
You set
Modules, inverters, strings
You get
DC/AC ratio, inputs in use
Model
Part-load inverter curve
Example
7.2 kW DC
on a Fronius Primo GEN24 7.7 · DC/AC 0.94
Shade & production
Every hour of a typical year at your address: light on the panels, heat, wiring and the inverter — and what each tree, chimney and neighbor takes from it, by month and by hour.
You set
Modules, tilt, objects
You get
kWh and shade loss by hour
Model
HDKR · Sandia · 145-patch sky
Example
12,239 kWh
a year · 0.5% lost to shade
Savings & payback
Every hour of sunshine is set against every hour of use, on your own rates. Get bill savings, payback, NPV and a 25-year cash flow — then compare variants side by side.
You set
Tariff, export rate, price
You get
Savings, payback, NPV
Model
Hourly net billing
Example
$2,186 / yr
saved · pays back in 9.1 years
PDF report
The whole calculation in one PDF: the site and its layout, production and shade by month, the variants side by side and 25 years of cash flow — with every input and data source behind them. Take it to an installer, or hold a quote up against it.
You set
One click on Export PDF
You get
A 16-page PDF to share
Model
Inputs, sources, model version
Example
16 pages
for the San Jose home · sample below
See the result for the San Jose home
From an address to a year of sunshine
No site visit, no sales call, no account. Find the house, draw what stands around it, and the whole year is calculated on your Mac in seconds.
1
Step 1
Find the site
Search an address anywhere on Earth or paste coordinates. The weather year for that spot loads by itself.
2
Step 2
Build the scene
Add the house and its roof, then the trees and neighbors. Trace over your own aerial photo when you have one.
3
Step 3
Place the panels
Set the module, tilt, heading and count. Drag the sun through the day and watch the shadows move.
4
Step 4
Read the year
Production, shade loss, savings and payback follow every change — by month and by hour.
5
Step 5
Compare & export
Save up to five variants, compare them side by side and take a PDF report to your installer.
8,760
hours simulated for every array
145
patches of sky traced for shade
5
design variants side by side
0
accounts, ads or subscriptions
Example calculation
One year of sunshine in a typical San Jose home
18 × 400 W panels · 7.2 kW
South roof · 40°
Home uses 10,800 kWh / yr
$0.40 in · $0.07 out
Solar generation
12,239
kWh / yr
1,700 kWh per kW on a PVGIS typical year — after shade, heat, wiring and inverter losses.
Home runs on its own sunshine
37%
of its yearly use
Use covered by the roof
37%
Solar sent back to the grid
67%
Saved on electric bills
$2,186
/ yr
The bill falls from $4,320 to $2,134. A $20,520 system pays for itself in about 9.1 years.
CO₂ emissions avoided
2.7 t
/ yr
At California’s grid average of about 0.22 kg CO₂ per kWh.
Why every hour matters: under NEM 3.0 the grid pays about $0.07 for each kWh you send it, but charges about $0.40 for each kWh you buy. SolarSolution Studio sets each hour of sunshine against each hour of use, so the savings count only what your home really uses itself.
Estimate, not a quote. Calculated in SolarSolution Studio for 18 Canadian Solar 400 W modules in two strings of nine on a Fronius Primo GEN24 7.7 inverter, on the south-facing 40° roof of a two-story house with a tall oak to the east; a PVGIS typical weather year for San Jose, 10,800 kWh annual use, flat net billing at $0.40/kWh import and $0.07/kWh export, and an illustrative $2.85 per watt system price with no incentive. Your own roof gives your own numbers.
Homeowners get honest numbers. Installers get a second opinion.
For installers · shade and yield in minutes
For homeowners · check a quote
Made on a Mac. Calculated on yours.
No account · no cloud · every input listed in the report
Full methodology
Data sources
What it doesn’t do
A whole year you can see
8,760
hours in every heatmap · straight from the app
Heatmap
Long summer days and short winter ones, cloudy weeks and clear ones — every hour of the example’s year in one picture.
Hours of production
Heatmap · kWh per hour, Jan to Dec
Heatmap
The tall oak’s shadow as a band across early mornings from April to September — more than half the year’s shade loss falls before 8 am. A monthly total would hide it.
Hours lost to shade
Heatmap · kWh lost per hour
App
Drag an arrow to move the array, a ring to turn it, and the slider to walk the sun through June 21.
The Layout screen
House, trees, panels and the sun
Chart
What the 18 modules deliver each month — August best at 1,201 kWh, December lowest at 643.
Production by month
kWh after every loss
App
Fewer panels make less but pay back sooner. Size, production, savings and NPV on one scale.
Variants side by side
18 modules against 14
App
A multi-page PDF with the site, production, shade loss, economics and every assumption behind them.
The report
Every section, live from the model
What’s inside every calculation
Published models, run for every hour of the year — and named in the app, in the report and here.
01
Sun & weather
Sun position
NOAA equations
Weather
PVGIS, NASA POWER or your file
Light on the panels
Hay–Davies–Klucher–Reindl
Ground
Reflected light, per array
02
Shade
Direct beam
Ray-traced, hour by hour
Sky
145-patch dome, per array
Trees
Deciduous crowns thin in winter
Shade loss
The year with and without objects
03
Energy
Module heat
Sandia open-rack model
Reflection
Incidence-angle correction
Inverter
Part-load curve, clipped at AC
Cross-check
Compared against pvlib
04
Money
Bills
Hourly, on your own tariff
Rates
Flat, time-of-use or tiered
Exports
Net metering or an export price
Returns
Payback, NPV, IRR and LCOE
Questions, answered
Does it work in my country?
Yes. Weather comes from PVGIS or NASA POWER for almost any point on Earth, and you can load your own hourly file. Automatic aerial imagery covers the continental US for now; elsewhere, import your own photo and trace over it.
Which Macs does it run on?
Is it really free?
Is this a quote or a guarantee?
Do I need exact roof measurements?
Does it model batteries?
Still have questions?
