No, the existing gas or oil boiler does not need to be replaced. re-green upgrades it to a hybrid system: the existing boiler stays in the building and only covers peak load on the coldest days, while the heat pump provides around 90% of the annual heat. If the heat pump fails, the boiler acts as full backup – heating is never interrupted. Radiators and heat distribution in the building remain unchanged.

re-green approaches tenants in close coordination with the property manager and the owner.

All tenants are free to choose their supplier. However, with low power prices and the installation and operation of charging points, re-green offers clear added value over conventional suppliers.

The energy management system controls the heat pump, PV system and charging infrastructure so that locally generated power is used in the building first rather than exported. It also provides precise consumption and generation data for service charge billing and sustainability reporting. Owners and property managers no longer have to manage or coordinate the building technology.

From the first business case to commissioning typically takes six to nine months. The critical path is usually approval by the distribution network operator, not construction time in the building. Prefabricated plant containers significantly shorten on-site construction. The building stays fully let and operational throughout.

Usually not. As standard, re-green inspects roof build-up, remaining service life, waterproofing and structure during the technical survey. Modules are ballast-mounted on the flat roof without penetrating the membrane, so roof warranties remain unaffected. If renovation is needed, it is scheduled before installation; the system can be dismantled in sections for later roof work.

That depends on the financing model. With contracting, re-green builds, finances and operates the PV system; the system and the power it generates belong to re-green, the owner invests nothing and receives a lease for the roof area. With owner financing, the owner invests and holds the system as a fixed asset; re-green handles operation and power supply, and the owner takes a significantly higher share of the returns. In both models, the power is supplied primarily to the building’s tenants. At our reference building in Duisburg, a 228 kWp rooftop system supplies tenants at 15 ct/kWh (unit price, plus network charges).

In the energy contracting model, the economic return is generated without any capital from the owner. It comes from four sources: lease income for roof and plant areas, avoided landlord-side CO₂ costs, eliminated maintenance and replacement investment for heat generation, and better lettability thanks to lower service charges. The effect flows straight into net operating income; re-green puts the resulting increase in market value at 10 to 20%. It applies regardless of holding period, as buyers deduct missing building technology as an investment backlog from the purchase price, while a building with a running system enters the sale process without this discount.

With contracting, re-green remains the owner of the systems, carries the full investment, refinances through power and heat supply contracts and handles operation and maintenance for 20 years; the property owner pays nothing. With owner financing, the property owner finances the systems, holds them as fixed assets and takes a significantly higher share of the returns. On request, re-green also handles operation and maintenance for 20 years; the operating contract can be terminated after 2 years.

That depends on tenants’ current power and gas contracts. As of October 2026, re-green’s contracting prices are competitive with new gas contracts. At our reference building in Duisburg, tenants pay 15 ct/kWh (unit price, plus network charges). Lower gross rents including heating strengthen the space’s competitive position and shorten void periods.

Yes. re-green analyses portfolios asset by asset and prioritises by economics, consumption profile and regulatory urgency. Standardised contracts and framework agreements allow parallel delivery across multiple assets.

The revised EU Energy Performance of Buildings Directive (EPBD) sets binding minimum standards for non-residential buildings only: the worst-performing 16% of the stock must be upgraded by 2030, the worst 26% by 2033. The reference point is the building stock as of 1 January 2020. Affected asset types include office, retail, hotel, logistics and warehouse properties.

Under Germany’s CO₂ Cost Allocation Act, landlords and tenants of non-residential buildings currently share CO₂ costs equally. The landlord’s share rises with the CO₂ price and cannot be passed on. The lower the fossil share of heat generation, the smaller this item in the owner’s P&L.

Smart meters and the energy management system provide precise consumption and generation data for heat and power at asset level. This feeds directly into CSRD reporting, EU Taxonomy assessments and CRREM pathway analyses. Consumption no longer has to be estimated or reconstructed from bills.

A property is considered stranded when its CO₂ intensity exceeds the decarbonisation pathway for its use type – usually measured against the CRREM pathway. From that point, it falls outside institutional investors’ acquisition criteria and only trades at a discount. Retrofitting a heat pump and PV lowers CO₂ intensity and keeps the asset on its pathway.

No. re-green acts as operator of the systems and provides the commercial service, while the owner remains in their role as landlord or lessor. The contracts have been reviewed by specialist real estate lawyers. For large properties, re-green additionally offers a lease payment structured to avoid any adverse effect.

In the energy contracting model, the systems remain the economic property of re-green and do not appear on the owner’s balance sheet. No fixed assets and no depreciation arise.

The contract transfers to the buyer. In our experience, buyers scrutinise a registered easement closely, but view a completed retrofit as an advantage over a building with outstanding investment needs. Alternatively, the buyer can buy out the systems and have the easement removed.

re-green fully handles operation, maintenance, fault resolution and billing for 20 years. Maintenance follows a preventive plan; for repairs, re-green works with established partner companies. Property managers and owners no longer have to coordinate the building technology.