Shinetime is built for the case where the surroundings decide the result: dense housing, a neighbour’s gable, trees, a slope.
01
Data basis
Everything that casts a shadow comes from a survey or is named as an assumption.
Official LoD2 building models of all sixteen German states, with recorded ridge and eave heights and real roof shapes. Courtyards and light wells are cut out, not filled in.
Where no LoD2 data exists, OpenStreetMap footprints are extruded with their heights. Where a height comes from is stated on the building: measured, from storeys, or assumed.
DGM1 terrain model from the same survey and the same vertical datum, so buildings stand on the ground rather than float above it. A 30-metre model worldwide as a fallback.
Trees from the tree register and OpenStreetMap with crown height and crown width. Six species to place yourself, each with a summer and a winter crown.
Hourly irradiance and temperature from PVGIS based on the SARAH3 typical year, for any place in the world. Precomputed cells for Germany; everything else is fetched on first use.
02
Shading
Two fields: the scene nearby and the terrain far away.
Shading across the day
The time slider across a winter day.
The shadow’s path across the day for any date, in the same scene you work in. The time slider takes the day and the year, across midnight too, and a year like 2040 can be typed in.
For the calculation, every module point is tested for every hour of the year against buildings, trees, terrain and everything you have placed: out to 4 km in the scene.
Beyond that, the terrain horizon: 360 directions, out to 50 km, with earth curvature and refraction. A ridge 15 km away, 7.6 degrees above the horizon, takes hours in winter.
Solar access as the share of hours actually in the sun, the visible sky fraction per face, beam and diffuse shares separately. The diffuse share is split into its three Perez components, each with its own obstruction.
When a tree or a neighbour changes, the affected face recalculates. What is unchanged stays put.
03
Layout
Modules are placed, not estimated.
Placing modules
Automatic layout, then finished by hand.
One click on the roof finds the whole roof face: every triangle in the same plane, out to the edge of the building. Semi-detached houses under one roof polygon are split at the parcel boundary.
On pitched faces the modules lie flat in rows along the eave. On flat roofs they stand racked at your tilt and azimuth, with a row spacing at which no row shades the next at noon on the winter solstice.
Edge clearance, chimneys, skylights and everything you place are kept free. Eight row offsets and both orientations are tried; the most modules win.
Move, delete, place by hand: modules snap to their neighbours, show their distance to the roof edge and stay on the face. Undo exists per roof face.
Modules from a selection of common formats, or with your own wattage and glass dimensions. Efficiency is derived from those, never typed, so a module cannot contradict itself.
Every module gets its own year. The weakest is named, modules below 80 percent of the best are reported, and on the roof you see them all coloured by yield.
04
Wiring
The electrics decide what is left of the light.
Three electronics on an open roof
The same modules, nothing in the way. kWh per kWp and year.
On an open roof, optimisers and microinverters lose their edge: both keep 99.3% per hour, the microinverter never more than its rated power. Where shade falls, the picture turns, and that is exactly what the map computes.
As a table
Category
kWh/kWp
String inverter
1,122
Optimisers
1,115
Microinverters
1,115
Strings per roof plane, never across planes, on the MPP inputs of the inverter. More strings than inputs go in parallel, at equal length where the count allows.
Cell strings with their bypass diodes are modelled: one shaded module in ten costs itself, a mostly shaded string drops to the current of the shade.
The inverter is picked automatically: the smallest in the catalogue whose voltage window and inputs carry every string and whose AC rating exceeds the kWp by at most 1.3 times. Or you pick yourself and are told what does not fit.
String lengths are checked against the voltage window: open circuit at minus 10 degrees below the maximum voltage, operation at 70 degrees above the lower MPP bound. Every exceeded limit is a warning.
String, optimiser and microinverter are always all three computed, in kWh per year, in extra cost over the string, and in euros per additional kilowatt hour over twenty years.
05
Household and battery
Hour by hour against consumption, with a battery in between.
An annual consumption and one of five load patterns. From these, self-consumption, feed-in and what is still bought.
Six battery sizes compared, the one with the highest return after twenty years marked.
Electricity price and feed-in tariff from the EEG by system size, or typed in. The cap on feed-in at 60 percent of the kWp without a smart meter is computed hour by hour; the battery charges first.
The electricity bill without and with the system side by side, and the balance after twenty years in whole euros.
With everything that it is: a sizing aid with fixed prices, no discounting, no ageing, a pattern instead of a meter. It says so on the map and in the report.
06
The report
One building per page, A4, to print or as a PDF.
The report
The report paging through: roof from above, faces, months, strings, battery, assumptions.
The roof from above with the modules in the colours of their strings, plus an oblique view.
The roof faces with tilt, azimuth, area and yield. The monthly curve. The module, the strings, the inputs with their voltages and currents.
The inverter comparison, the battery comparison, the electricity bill.
And at the end the assumptions. All of them. So the report holds up in a conversation.
What is declared
Every assumption is stated next to the number
If a flat roof face was set at 30 degrees facing south, it says so there. If a building without a measured height was extrapolated from storeys, it says so on the building. If the inverter is too small for the kWp, it says so on the map and in the report, in amber, and stays until you have changed it.