WPOpt4Grid

Technical and social challenges in the grid-friendly and economic optimization of heat pump systems

Heat pumps are a key technology in the heating transition. As electrical power consumers that supply heat for households and industry, for example, they can also make an important contribution to sector coupling. The economic optimisation of heat pumps is the most important factor for market success. However, this is relatively complex, as the COP is highly dependent on ambient conditions.

Surpluses in electrycity generation due to high renewable production are becoming more common, which limits their usability. Heat pumps can utilise these surpluses to benefit the system and the grid thereby operating more economically over their life cycle.

Time-dependent electricity tariffs are currently rarely used, and particularly in the over-50 kW range, little research has been done into the effects of dynamic electricity prices and how heat pumps can be optimised to respond to them.

Fluctuating electricity prices mean that heat pumps with an optimised SCOP are not automatically the most economically solution. Relevant influencing factors include:

• Dimensioning
• Control strategy
• Heat source
• Technical restrictions (on-off times, cycling, ramps)
• Interaction: heat demand profile - generation profile - storage masses
• Usage requirements (comfort, et cetera)
• Tariff model

The main project objective is to analyse from various perspectives such as

• GHG emissions,
• energy generation from renewables in the electricity system (energy system model),
• load shifting potential,
• storage requirements in the electricity system (energy system model or comparison with pumped storage and batteries),
• annual performance factor
• longevity of the heat pump system and
• user requirements (comfort, process reliability, et cetera)

to investigate the extent to which the economically optimised dimensioning of heat pump systems over the life cycle is desirable in the case of time-varying electricity prices in the context of spot and balancing energy markets.

To this end, generic case studies will be selected to cover a broad spectrum within the following framework:

• Required heat output over 50 kW
• Commercial operators
• Three types of buildings or uses: for example large residential complexes, non-residential buildings (commercial, schools, museums, hotels), industrial process heat
• Various heat sources (air, geothermal, waste heat), distribution systems (air, radiators, underfloor heating, component activation) and, where applicable, storage systems (water and ground source heat pumps); up to eight relevant combinations will be selected with stakeholders and then simulated and optimised.

The following questions, among others, need to be clarified:

• Which heat pump design is economically optimal depending on the electricity tariff model?
• Which tariff models can facilitate participation in short-term markets (control reserve, intraday trading, balancing energy minimisation)?
• Which control strategy should be chosen to make the best use of time-dependent electricity tariffs?
• How much efficiency is lost with an operating mode that is economically optimised for time-dependent electricity tariffs?

With regard to energy markets, at least three use cases will be developed and translated into a control strategy. The heat pump system of each case study will be optimised for each use case.

Furthermore, legal, financial and information-related deficits will be analysed in interviews with market players and an analysis of existing findings, and solutions will be developed.

This project will lay the foundation for the implementation of a system-oriented heat pump approach, including monitoring, in real projects.

Client / Funding organisation	FFG on behalf of BMIMI and BMWET
Project management	Franziska Zimmer
Project team	Petra Lackner Konstantin Kulterer Franz Zach
Project partners	AIT Austrian Institute of Technology GmbH
Project duration	May 2025 to April 2026