De kosten en baten van warmteopslag in warmtenetten (2024)

The Costs and Benefits of Heat Storage in District Heating Networks

Why was this study conducted?

Kalavasta has been comissioned by Invest-NL and Energy Storage NL to assess whether thermal storage can provide both financial and societal added value for district heating networks in the Netherlands. With the goal of climate neutrality by 2050, district heating networks are seen as an important solution, but they need to be sustainable, affordable and well-integrated into the energy system.

What key technologies were analyzed?

The study examined three main types of thermal storage: Aquifer Thermal Energy Storage (ATES) for underground seasonal storage, Tank Thermal Energy Storage (TTES) for short to medium term storage in insulated tanks, and Pit Thermal Energy Storage (PTES) for storage in insulated underground pits. These were analyzed across three different district heating configurations varying in size, temperature level, and heat production mix.

How was the study conducted?

A techno-economic model was developed to calculate hourly heat demand and supply patterns and analyze the deployment of thermal storage. The model compared district heating networks with and without storage across three test cases in the context of the Dutch IP2024 National Drivers 2035 scenario, which describes future developments in the energy system.

What were the key benefits identified?

The study found that well-dimensioned thermal storage reduces heat production costs through reducing gas consumption and peak boiler capacity needs. It also lowers emissions by reducing reliance on gas boilers. Storage enables more efficient use of renewable electricity, reducing curtailment of wind and solar by 150-200%. Finally, thermal storage can help reduce grid loads by enabling more flexible heat pump operation. However, the analysis found that current proposed discounts on grid tariffs for "non-firm" grid connections are insufficient to cover the additional costs.