Simulation lab · Breda, NL · 8 to 40 households
Solarpunk, with the math done.
SolarPunkLab is a living simulation of a self-sufficient neighbourhood: energy, water and community in one balance model that closes every tick. Read what actually works, what does not, and what it costs. Built on real Dutch weather years, with every assumption labelled and every number open to attack.
Read the lab log
Four numbers from the lab
Factor 9
Seasonal storage breaks the winter wall: 90% self-sufficiency including heat drops from 117,000 to 12,900 euros per year.
LP run · base-8 + heat · weather year 2022 · A48: low confidence
±2039
The earliest crossover year in which building new becomes cheaper than renovating, under aggressive construction automation.
K series · aggressive automation · without automation: ±2054
26%
The ceiling on rainwater self-sufficiency. Bigger tanks do not help; the ceiling sits in the greywater split.
greywater ceiling 36.8% · 2018 drought · daily profile A28
+363 kWh
What a free rider draws from the shared neighbourhood battery each year under an open pool. The right sharing rules cut that in half, or reverse it.
open pool · pro-rata rule: +204 · archetypes A32 to A34
✓ Balance closed · every number above comes from runs whose hourly energy balance closes to machine precision
Why this lab
A vision becomes real when the balance closes
Thousands of people share dreams of self-sufficient communities. Almost nobody says: I built it, I ran the numbers, and here is the honest answer. Even when that answer stings.
SolarPunkLab does exactly that. The lab simulates a neighbourhood of eight to forty households, anchored in Breda, the Netherlands, on real weather years from the Dutch national weather service and official consumption profiles. Every outcome has to obey physics: the energy balance closes every hour to machine precision, and an accounting trick never beats a law of nature.
The dream images stay. But under every image on this site sits a number, and under every number an assumption you can check.
The model
Three layers, one balance model
Everything is connected: the heat pump drives winter demand, the water profile feeds hot-water heat, the sharing rules decide who drains the battery. So the lab computes them together, not in separate single-purpose tools.
Energy
Solar on every roof, a shared neighbourhood battery, dynamic prices, heat pumps and seasonal storage. Computed hour by hour; a full year runs in a tenth of a second.
Water
Rain harvesting, retention and greywater splitting, stress-tested on the real 2018 drought. Including sewer overflow during cloudbursts, the number municipalities actually plan around.
Community and governance
Simulated households and three Ostrom rule sets side by side. Behaviour changes demand, rules change distribution; the lab keeps those two strictly apart.
The crossover model
When does building new become cheaper than renovating? The starting condition is that renovation wins today, in line with the evidence. If you find a crossover, you set the assumptions yourself and you can defend them.
First the contract, then the numbers
Every number on this site is bound by an honesty contract: assumptions labelled with source and confidence, starting conditions that work against the vision, and balances that close. Read how that works before you believe any of the results.
Read the honesty contract