Costs & funding
Compare all the costs.
Make an informed decision.
What will your project cost to install, run and maintain over the years? Organise quotes, make assumptions explicit and find the right route to funding.
The essentials
- The same task: A meaningful comparison requires quotes with the same scope, time horizon and price date.
- All the costs: Installation, ongoing operation and later expenses belong together. Missing information stays unresolved.
- Check funding early: Clarify conditions and the required sequence before making a binding decision.
On this page
01 · The same starting point
Two quotes need to address the same task.
First describe what the solution must deliver. Then compare options for the same household, building condition and time horizon.
- Performance and use: Which rooms need heating, how far will you drive, or what electricity demand should be covered?
- Scope: Which devices, work, registrations and services are included up to handover of a ready-to-use system?
- Time horizon and price date: Use the same number of years, the same price date and comparable final amounts, including VAT where applicable.
- Missing items: Mark items as “included”, “quoted separately” or “still to clarify”. An unknown amount is not zero euros.
- Shared work: Count scaffolding, cable routes or meter alterations only once in the overall comparison. Show the costs of renovation already planned separately.
02 · The complete calculation
Upfront costs, ongoing operation and cash flow.
Upfront
Equipment, installation, planning, site work, connection, necessary alterations and commissioning. Ask for optional extras and excluded services to be listed individually.
Annually and later
Energy, standing and metering charges, maintenance, services and insurance where additionally required. Also record possible replacement investments within your comparison period.
Funding and finance
A grant can reduce your own financial contribution. A loan must be repaid. Payment dates, interest and any bridging finance belong in your payment plan.
Costs and monthly payments are two different views
The cost comparison includes the investment and any financing costs. Do not count the purchase already recorded a second time as loan principal repayments. For your monthly budget, look instead at the instalments, bills and income actually due.
Record expected, applied-for, approved and paid grants separately. An announced grant is not yet money in your account.
A saving is not additional income
Buying less electricity from the grid saves purchase costs. Payment for electricity fed into the grid is a cash inflow. The same kilowatt-hour cannot be both used at home and exported. Higher self-consumption alone also does not demonstrate that a battery is financially worthwhile.
Fictional sample bill · not a tariff recommendation
Read four key figures from your electricity bill.
Closing meter reading 15,450 − opening reading 12,450 = 3,000 kWh. Period: 1 January to 31 December of an example year.
3,000 kWh × €0.30 = €900 usage cost. Use this price per kWh for extra grid electricity, for example in the charging cost calculator.
This fixed charge is independent of kWh used. Do not allocate the existing household standing charge to the EV again in full. Compare additional or changed fixed charges separately.
All example prices include tax. €1,044 ÷ 3,000 kWh = 34.8 ct/kWh is an average including the standing charge; it is not the unit price of 30 ct/kWh.
Monthly payments are advance payments.
Here, 12 × €90 = €1,080 was paid. Against annual cost of €1,044, this leaves €36 credit. Real bills may use a different number or amount of payments. The monthly payment alone does not reveal your unit price.
Record your billing period, kWh, gross price per kWh and additional fixed costs separately. Our calculators do not need your customer number, address or bank details.
What belongs in the comparison for your topic?
Heating: provide the same useful heat
Compare a heat pump and district heating as concrete alternatives only if both are options for your building and schedule. Define the point at which delivered heat is measured and how hot water, storage losses and distribution losses are included.
- Heat pump: a justified heat quantity and seasonal performance factor (SPF, “JAZ” in German), the resulting electricity demand, plus standing and metering charges, maintenance and all necessary installation work.
- District heating: building connection, substation and alterations; during operation, the heat unit price, standing or capacity charge and other contractual costs.
- Questions to ask: Are temperatures, building condition, auxiliary heating and price adjustment rules clear? Do not equate gas or oil consumption with useful heat without checking.
Prepare the heating comparison with professional advice → · Ulm’s heat plan and the connection question →
Solar PV: assess the battery as a separate additional decision
Start by comparing a PV system with the same system plus a battery. Use identical assumptions for the roof, generation, household consumption and electricity price. Only the battery’s additional benefits and costs belong in its comparison.
- Show generation, direct use, storage including losses, and grid export separately.
- Record additional costs for the battery, compatible equipment and possible replacement.
- If an electric car or heat pump will be added later, calculate both a current and a future usage scenario.
Electric mobility: record charging costs and vehicle costs separately
Compare the same mileage and a realistic mix of home and public charging. A home charger quote should include electrical work, cabling and any shared basic infrastructure. Public charging may involve additional fees.
A comparison of whole vehicles also includes purchase or depreciation, finance, insurance and other running costs. Our charging calculators cover only charging electricity or charging tariffs.
Prepare for a home charger → · Clarify costs in a shared building →
Solar PV and taxes: two different questions.
VAT when buying
Since 2023, qualifying PV supplies and installation have been subject to a VAT rate of 0 per cent. This can include essential components and suitable batteries. Systems on or near residential buildings qualify; 30 kWp is a statutory simplification threshold, not a universal upper limit. Maintenance contracts do not automatically qualify.
Income tax during operation
Section 3 no. 72 of the German Income Tax Act (EStG) exempts qualifying income and withdrawals from building-based PV. The current limit is 30 kWp per residential or commercial unit and a total of no more than 100 kWp per taxpayer or business partnership. The amended provision applies to systems acquired, commissioned or expanded after 31 December 2024; different limits apply in some older cases.
For your records: Record purchase and commissioning dates, expansions, capacity registered in the Marktstammdatenregister (MaStR), building units and any other systems. The 100 kWp limit is an exemption threshold, not a tax-free allowance. A purchase with 0 per cent VAT does not resolve all income tax questions or determine the VAT treatment of subsequent operation. Clarify older systems, multiple systems and special tax cases with the tax office or a tax adviser.
Sources checked on 28 September 2026: Section 12(3) UStG · BMF: VAT on solar PV · Section 3 no. 72 EStG · Section 52(4) EStG.
Buy, finance or rent solar PV?
Buy with your own funds
Record the full purchase price and running expenses. Agree who will handle servicing, repairs and insurance. The capital used is no longer available for other projects.
Buy with a loan
Also check interest, fees, the loan term and any final balloon payment. Principal repayments spread the purchase price across payments; they must not be counted again alongside the purchase price in the total cost calculation.
Rent or lease
Compile all payments over the contract term, additional costs and agreed services. In particular, check repairs, downtime, sale of the house, and removal or ownership transfer at the end of the contract.
Compare the same equipment, scope and period of use. Low monthly payments do not demonstrate low total costs. The zero VAT rate for PV does not apply to rental; the treatment of leasing and hire purchase depends on the contract. Our PV quote calculator compares purchase prices in quotes for buying systems and does not cover rental contracts.
Sources checked on 28 September 2026: Verbraucherzentrale: reviewing rental contracts · BMF: rental, leasing and hire purchase.
03 · A hypothetical example
The cheaper purchase is only part of the calculation.
Two options perform the same task. The chart shows how upfront and running costs add up over the period of use.
Consider upfront and running costs together
A: €12,000 upfront + €1,600 per year. B: €18,000 upfront + €1,000 per year. Entirely fictional figures, unrelated to any particular technology.
Calculation values in a table
| Years | Option A | Option B |
|---|---|---|
| 0 | €12,000 | €18,000 |
| 5 | €20,000 | €23,000 |
| 10 | €28,000 | €28,000 |
| 15 | €36,000 | €33,000 |
The takeaway: After ten years, the two options are equal. For a shorter period of use, A is cheaper; for a longer period, B is cheaper, under precisely these assumptions.
What happens if an assumption changes?
If B costs €1,200 per year instead of €1,000, its total after ten years is €30,000. A remains at €28,000 in this example. Changing just one assumption changes the result.
For real quotes, therefore also ask for a scenario with higher energy prices and one with lower savings. For heat pumps, the SPF matters; for PV and batteries, the solar electricity that can actually be used matters.
Ten years is a calculation point here, not a statement about service life. For real quotes, add the cost categories excluded from the chart.
04 · Official funding routes
Which route fits your project?
Check with the responsible funding body: is the programme open, who can apply, which costs qualify and what procedure applies? The funding rate applies to recognised eligible costs within programme limits, not automatically to the entire bill.
Cars & charging
Electric car funding in 2026
For private individuals buying or leasing eligible new cars. Vehicle type, taxable household income and children affect the funding. Used cars are not covered by this programme.
Check the conditions and application steps with the federal environment ministry →
Checked on 28 September 2026: Applications have been possible since 19 May 2026; first registration from 1 January 2026 is decisive. Check eligibility requirements and evidence before deciding to buy.
What is the procedure?
First check the conditions, then acquire and register an eligible vehicle. Afterwards, submit the digital application to BAFA through Förderzentrale Deutschland. Follow the application deadlines and minimum ownership periods on the official website.
In the vehicle comparison, enter only a confirmed separate grant or an explicitly labelled assumption. Do not double-count benefits already deducted. Also calculate a scenario without any unconfirmed grant.
Charging in apartment buildings
For owners’ associations (WEGs) and other eligible owner and business groups. The programme covers shared charging infrastructure at existing apartment buildings; an individual private home charger does not automatically qualify.
Open funding calls and applications for apartment buildings → · BMV: deadlines
- Open until 10 November 2026 (calls 1 and 2): owners’ associations, SMEs and eligible private owners, subject to available funds.
- Closed on 15 October 2026 (call 3): The application deadline for companies with large housing portfolios under the competitive procedure has passed.
Funding status according to the programme portal, checked on 27 October 2026. The current conditions of the relevant funding call and its technical requirements apply.
How do I proceed?
Prepare documents and apply, wait for approval, then commission the service and carry out the work; afterwards, submit the evidence. As a tenant, first discuss the project with your landlord or property manager.
Heating & renovation
Heating or a heat network
KfW 458 is aimed at private owners and owners’ associations of existing residential buildings. A connection to a building or heat network may also qualify. Requirements, bonuses and maximum amounts depend on the project.
Insulation and renovation
BAFA provides routes for individual measures on the building envelope, certain building services, heating optimisation and related professional planning. Check the relevant measure category and whether an energy efficiency expert must be involved.
Solar PV
Solar PV and finance
KfW 270 is a loan programme for renewable energy, such as PV systems and batteries. Private applicants must export or sell some of the electricity generated. Plug-in solar is excluded. Compare the terms with other financing options.
Solar PV and grid export
Payment for electricity fed into the grid forms part of ongoing revenue. Relevant factors include the commissioning date, system size and export arrangement. The Federal Network Agency publishes the applicable rates; check separately for later commissioning dates.
External · co2online
Which funding fits my project?
Have ready: Information about the building and your renovation plans. FördermittelCheck identifies suitable programmes, contacts and whether support is a loan or grant, and provides a funding roadmap.
Afterwards: Check each result with the funding body for eligibility, conditions and the required sequence. The tool provides guidance; a result is not a funding approval.
Sources checked on 28 September 2026: Provider’s description of FördermittelCheck.
External · KEA-BW
Find other funding programmes in Baden-Württemberg
The KEA-BW search brings together funding programmes, including many for municipalities and businesses. For each result, check whether private individuals or owners’ associations are eligible. Conditions and application steps are set out by the funding body.
Have ready: Project, location and applicant group, such as private owners or an owners’ association.
Find home charger, plug-in solar and other programmes
Search the federal funding database by project, region and target group, such as private individuals or owners’ associations. Then read the funding body’s current original page. An old programme or a general search result does not establish that applications are possible today.
Combine several grants or tax benefits?
Before calculating, have the permitted combinations for the same measure and the allocation of eligible costs checked. You cannot simply add programmes and tax benefits together. Record the checked combination, date and responsible body.
New funding routes for electric cars and apartment buildings: checked on 28 September 2026. The other routes were checked on 19 September 2026. Check conditions and application steps again with the relevant funding body before making a binding decision.
Ulm · checked on 19 September 2026
Ulm’s funding programme has been suspended.
The City of Ulm reports a suspension of applications and funding since 1 September 2026. For a new project, you should therefore currently not count on a confirmed municipal grant from this programme.
Applications already submitted have a different status from new projects. Clarify your specific case with the city. Check the official programme page for any possible future reopening.
Official route: City of Ulm: current status of the energy funding programme
Check federal programmes separately against their own requirements and current status.
05 · Clarify the procedure
The sequence depends on the programme.
First clarify the funding route with your contractor, energy adviser or financing partner. Agree who will prepare each confirmation, submit the application and compile the later evidence.
For electric cars and charging infrastructure in apartment buildings, the checked steps appear directly in the relevant funding cards: Electric car funding: requirements and application steps · Funding for charging infrastructure in apartment buildings. The following procedures apply only to the programmes named.
KfW 458: prepare the heating grant application
- Involve a specialist contractor or energy efficiency expert and have the application confirmation (Bestätigung zum Antrag, BzA) prepared.
- Prepare the required supply or service contract with the funding condition required by the programme and the planned implementation date. This condition must not be added retrospectively.
- Apply through “Meine KfW” before starting the project. Responsibility differs, including between an individual house and an owners’ association.
- Carry out the work after approval, then submit the required invoices and confirmations within the stated deadlines.
Official route: KfW 458: heating grants and application steps
BAFA: prepare individual renovation measures
- Clarify the appropriate measure and technical requirements; have the required technical project description (TPB) prepared.
- Before applying, agree the required contract with its funding condition and implementation date.
- Apply through the BAFA portal. According to BAFA, starting after application but before approval is at your own risk.
- After completion, compile invoices and the technical project verification (TPN) for the proof of use; observe the deadlines in the approval notice.
Official route: BAFA: current application procedure
KfW 270: arrange the loan through a bank
Apply through a financing partner. According to KfW, you must do so before entering a legally binding contract for the project. Only after approval do the loan agreement and project start follow under the prescribed procedure. The heating grant procedure cannot simply be applied to this programme.
Official route: KfW 270: renewable energy loan
For your notes: Programme and date checked · applicant · required confirmation · contract step · application · approval · start · evidence · payment. Record the responsible person and deadline for each point.
Your result
One template for every quote.
Copy these points into your notes and complete them for each option. Ask for missing amounts to be added before using a total as the basis for your decision.
Task and costs
Option and supplier: …
Same task / building / use: …
Time horizon and price date: …
Total upfront costs: …
Of which optional or still unresolved: …
Annual: energy / fixed costs / maintenance: …
Later replacement costs and residual values: …
Assumptions and next step
Use, energy prices, efficiency / yield: …
Funding: expected / applied for / approved / paid: …
Finance and payment dates: …
Result under different assumptions: …
Missing answer / responsible body: …
Next step and date: …
Add the source of every important figure: a quote, energy bill, tariff sheet or explicitly stated assumption. This makes it possible to update the calculation later.
Calculate with your own figures.
Use the charging cost calculator to compare two charging scenarios with your mileage, electricity demand and prices. A separate public charging tariff comparison also includes additional fees.
Both calculators cover charging costs. Purchase, finance and other vehicle costs belong separately in your overall comparison.
Compare two vehicles in full
The total vehicle cost calculator adds the purchase price, expected resale proceeds, finance and running costs. Compare two purchases, or keeping your car versus buying another, using the same period and mileage.
Heating: compare investment and operation together
Go to the heating quote comparison → Compare the same heat supply over the same period, including investment for both options, assumed grants and annual operation. You can explicitly add finance, repairs, replacements and residual value. Prices remain constant in the scenario; missing costs remain unresolved.
External · co2online
Which renovation deserves a closer look?
ModernisierungsCheck compares renovation measures using modelled costs and savings. Use the result to select suitable options for an advice session; obtain actual quotes afterwards.
Have ready: A heating bill showing the period and consumption, plus information about the building and previous renovation work.
Afterwards: Take results and unresolved questions to an adviser →
Clarify the biggest unresolved question first.
You may be missing a connection quote, a sound consumption assumption or the responsible funding contact. Take that specific point into your next discussion. The Regional Energy Agency Ulm helps you assess your projects; quotes, technical design and funding decisions come from the bodies responsible for each.
Sources and context
- KfW 458: heating grants and application steps
- BAFA: renovating residential buildings
- BAFA: current application procedure
- KfW 270: renewable energy loan
- Federal Network Agency: EEG support and payment rates
- City of Ulm: current status of the energy funding programme
- Federal funding database
- Regional Energy Agency Ulm
Existing content: editorial and source review on 19 September 2026. Newly added sections carry their own review dates; PV taxes, buying/renting and FördermittelCheck were checked on 28 September 2026. The numerical example is a freely chosen calculation exercise. Check programmes, terms and deadlines with the responsible body at the time of your project. The comparison template you can copy does not store entries on this page.