Predict your heating costs and regulations before they cost you €20k+
German homeowners and tenants face massive financial uncertainty from either high upfront heat pump costs or rapidly rising gas/oil heating expenses (projected to double by 2040) due to shifting regulations and green fuel mandates.
Heizwise lets German homeowners and landlords enter basic property details to run accurate 15-year cost simulations for heat pumps, gas, district heating, and pellets. It automatically factors in current subsidies, GEG regulations, and energy price forecasts to deliver clear recommendations and scenario comparisons.
German homeowners, landlords, and tenants in residential buildings facing heating system replacement decisions
Live regulatory feed combined with hyper-local German climate and grid data for projection accuracy no free government calculator can match.
supportive
Guided questionnaire for house size, age, insulation, current system and location
Calculates 15-year costs under mild, medium and strict regulatory scenarios
Checks KfW, BAFA and state-level grants applicable to your Bundesland
Charts showing break-even points, cumulative costs and savings
Professional downloadable report with next-action checklist
Automatically refreshes forecasts when energy prices or laws change
Email notifications when new rules affect your specific situation
Landlords can manage 5+ buildings in one account
Ask follow-up questions about any part of your report
| Column | Type | Nullable |
|---|---|---|
| id | uuid | No |
| text | No | |
| name | text | Yes |
| created_at | timestamp | No |
| Column | Type | Nullable |
|---|---|---|
| id | uuid | No |
| user_id | uuid | No |
| postcode | text | No |
| size_sqm | int | No |
| construction_year | int | Yes |
| current_system | text | No |
| insulation_rating | text | Yes |
| annual_consumption_kwh | int | Yes |
Relationships:
| Column | Type | Nullable |
|---|---|---|
| id | uuid | No |
| property_id | uuid | No |
| scenario_type | text | No |
| results_json | text | No |
| created_at | timestamp | No |
Relationships:
| Column | Type | Nullable |
|---|---|---|
| id | uuid | No |
| user_id | uuid | No |
| stripe_id | text | Yes |
| tier | text | No |
| status | text | No |
| current_period_ends | timestamp | Yes |
Relationships:
/api/propertiesCreate or update property profile
/api/simulateRun cost simulation engine
/api/subsidies/checkCheck eligibility for all applicable grants
/api/reports/pdfGenerate and return PDF report
/api/dashboardFetch latest simulations and alerts
2 simulations/month
None
20 properties
| Month | Users | Conversion | MRR | ARR |
|---|---|---|---|---|
| Month 1 | 140 | 9% | $366 | $4,392 |
| Month 6 | 920 | 17% | $4,527 | $54,324 |
Accurate 15-year forecasts tailored to German regulations, subsidies and your exact property.
1. Offer free Pro access for 30 days to members of the 5 largest German Facebook groups for homeowners and heat pumps in exchange for a video testimonial. 2. Contact 15 energy advisers on LinkedIn in Berlin, Munich and Cologne offering 30% recurring commission for referrals. 3. Run €300 Google Ads campaign on 'Wärmepumpe Kosten Rechner' and 'Heizung Austausch 2025' funnelling into a lead magnet simulation.
Huge reach and government-backed data
Generic one-size-fits-all calculators, no ongoing updates or personalized scenarios
Continuously updated personal forecasts with scenario modelling
Strong installer network
Biased toward partners, limited regulatory depth
Independent analysis focused purely on long-term financial outcomes
Monthly-updated proprietary regulatory ruleset + user-generated outcome data that improves recommendation accuracy over time
GEG 2024 mandates and the looming 2030-2045 fossil fuel phase-out have created urgent decision pressure for 4+ million German residential buildings in the next 5 years.
Users act on advice that later changes with new laws
Prominent disclaimers + 'last updated' dates on every report
Homeowners delay decision and never pay
Strong free tier that demonstrates clear value and creates urgency
Simulation engine produces unrealistic numbers
Validate against real installations from public datasets and offer conservative defaults
Success: ≥65% say they would pay €29/mo for personalized forecasts
Success: NPS > 35 and ≥12% convert to paid within 14 days
Success: ≥180 signups and €1,200 MRR in first 30 days
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