SlimmeWoningPlanner.nl
From energy-bill anxiety to "I know exactly what I can save"
The story
Before
Consumers want to make their homes more sustainable but don't know where to start. Solar panels? Heat pump? What really saves money? Installers give different advice. There is no independent simulation that looks at their specific situation.
Obstacle
Every home is unique. Postcode, year of construction, orientation, consumption: everything influences the savings. Generic calculators lie. Installers sell what they want to sell. Who gives honest advice?
Insight
Build a platform that simulates based on real data. Open data banks (cadastre, energy labels) plus user input form a personal savings plan. Independent, transparent, honest.
After
6 months on: platform live. Consumers simulate solar panels, batteries, going electric. They see what it yields, also after 2027. First successful connections with installers.
The first 14 days
From concept to working prototype.
Discovery: what do people want to know?
We talk to homeowners. "How much do solar panels really save me?" "Is a heat pump worth it?" "What if I switch to electric driving?" We map the questions that keep coming back.
Identifying data sources
Cadastre for home data. Energy labels database. Dynamic electricity price API. Postcode.nl for regional data. We build the data backbone.
Home profile design
What do we need to simulate? Year of construction, type, m², orientation, current consumption. Easy to fill in, but enough data for accurate calculations.
Simulation engine basics
Formulas for solar panel yield. Based on postcode (sun hours), roof orientation, number of panels. We test with known homes to validate.
Open data integration
Automatically retrieve energy label via API. Cadastre data for home type. Average consumption per type and year of construction. The user has to enter less manually.
UI for postcode scan
Type postcode and house number, immediately see what we already know. Fill in what's missing. No endless forms, smart defaults where possible.
First simulation: solar panels
Input: number of panels, type, orientation. Output: expected yield per month, payback time, savings also after 2027. With source references for every calculation.
Add battery simulation
What if you add a home battery? How much more self-sufficiency? When is it worth it? Simulate different scenarios.
Electric driving impact
You're switching to electric. What does that mean for your energy consumption? Charging at home vs home battery vs dynamic tariff. Calculate everything.
Installation documentation feature
Users can record their existing installations. Boiler, solar panels, router. With photos, warranties, manuals. Useful when an installer visits.
Share with installer
Generate secure share link. Installer sees your home profile, not your personal data. They can directly make a solid quote.
Personal savings plan
All simulations together: what yields the most for your situation? Prioritisation on ROI. Downloadable as PDF to share.
Privacy and data encryption
Home data is sensitive. Everything encrypted. Anonymous calculations. If data is intercepted, it can't be traced back to a specific home.
Soft launch with first users
We go live with friends and family. Real homes, real simulations. How accurate are our predictions? We collect feedback.
1-3 months later
Month 6 milestone: first real connections
The platform has been live for 6 months and performed 500+ energy scans. The big milestone: a few customers have been manually connected to installers for solar panels and home batteries. Not the main goal, but valuable validation. The simulations are accurate enough that people trust them for €10k+ investments. The coming months: automating this connection, more installers on board, and developing the "chore planner" feature where users get tips from other users.
1 year later
Vision: the independent energy advisor for the Netherlands
In a year we want SlimmeWoningPlanner to be the first place where people start with sustainability. Simulate, plan, document, request quotes. All in one place. The chore planner helps with questions to ask your contractor ("don't forget insulation when adding your veranda"). A network of trusted installers. But always independent: you can download the plan and go to your own contractor. We facilitate, we don't force.
"I didn't know if solar panels would still be worth it after 2027. The simulation showed: yes, even without netting. I've now ordered panels and a battery via their installer connection. Transparent and honest advice."