TU Delft builds local, CO2-free energy system for built environment

The idea behind it is simple, says Marjan Kreijns, director of The Green Village. 'The 24/7 Energy Lab is a local, CO2-free energy system. And that is much needed. After all, the built environment currently accounts for 35 per cent of the Netherlands' energy demand. If we succeed in making it partially CO2-free, we will take a giant step in accelerating the energy transition.'

A neighbourhood with a local energy system, with no CO2 emissions and no load on the national energy grid. It sounds like the distant future. However, preparations are already in full swing on the TU Delft site. Project leader John Schmitz says: "At TU Delft, an incredible number of scientists are working on the energy transition. In the 24/7 Energy Lab, all these different lines actually come together. A wonderful step we are taking is that we are launching the 24/7 system on Friday 14 January. Not much later, we expect to have made the electricity supply for one household CO2-free based on solar energy.

Good to know: this is a one-person household with no natural gas connection and consuming about 2,200 kWh per year. In a later phase, we will use the residual heat released to heat the other houses on the site. In three years' time, we want all of The Green Village to be supplied with locally generated energy from renewable sources. If that succeeds, we would like to scale it up to neighbourhood/neighbourhood level.'

For a large-scale transition to energy-autonomous neighbourhoods, it is necessary that politicians also get moving. There are still many legal restrictions, especially around the use of hydrogen. 'Both heat, electricity, and gas laws lag behind technology,' says Kreijns. 'There is a strong need for more leeway from politics in The Hague to allow innovations to develop further.'

There is also a major shortage of skilled personnel looming. It is also important that the new energy system is both economically feasible and accepted by residents. Kreijns: 'This is where The Green Village occupies a unique position as a living lab. Twelve people currently live there, and their user experience is very valuable in developing a user-friendly system'.

The big technical challenge lies in tying all kinds of components together, and controlling them. Electricity, gas and heat currently flow through the streets separately from each other, but that is going to change. A stable, sustainable energy system requires conversions between electricity, hydrogen and heat, each with its own buffering capabilities. You also need, for example, inverters to connect solar panels, which supply direct current, to a network of alternating current.

A central role in the project is played by the Electronic Management System (EMS). The EMS will control the various technical components. Taking into account as many variables as possible, such as the weather at the time, the weather forecast and the expected demand and supply. Schmitz: 'The EMS should use intelligent algorithms to answer questions such as Am I going to convert the currently generated energy into hydrogen or should I charge the electric car first? Such an integrated system does not yet exist, but is crucial to ensure that the supply reliability of this new, local, CO2-free system will soon be as high as the supply reliability of the conventional system. The Netherlands is used to more than 99.9 per cent delivery reliability, we have to match that.'

Illustration: A central role in the project is played by the Electronic Management System (EMS) that will control various technical components. (Illustration: Stephan Timmers)
Source: TU Delft