We are sitting on an energy reserve we are literally building over
Google’s headquarters in California covers its heating demand using ‘energy piles’ installed in the ground. This solution is barely mentioned in the Norwegian debate.
The construction pit at Campus Ullevål, where Norway's first energy wall has been integrated into the foundation. These walls will store and reuse heat from the ground beneath the new headquarters, which is scheduled for completion in 2026. ( Photo: Mari Svenningsen)
When Google built its vast headquarters in California, around 2,500 so-called “energy piles” were installed in the ground. The result is that the building’s foundation now covers 95 per cent of its cooling demand and the entire heating demand. Experiences like this demonstrate the effectiveness of utilizing the ground as an energy store to alleviate pressure on the electricity grid.
Norway has a unique position in that we use a significant amount of electricity for heating. According to the Norwegian Water Resources and Energy Directorate (NVE), approximately 80 percent of electricity consumption in homes is used for space heating and hot water.
The government’s action plan for energy efficiency calls for greater local energy flexibility and increased storage capacity to alleviate grid pressure. The paradox is that the solution Google has implemented — and which quite literally lies beneath our feet — is barely mentioned in the Norwegian debate.
The ground becomes a seasonal storage
The energy logic in many large buildings today is far from sustainable. In the summer, we use electricity to eliminate surplus heat, which we then have to purchase back when winter arrives. A valuable resource is lost when it could be stored instead.
The solution is energy foundations. These are foundations that serve two purposes simultaneously: they support the building structurally and function as a thermal battery.
The principle is simple. Water-based pipe loops are installed in piles or retaining walls in the excavation pit. Surplus heat from summer cooling is stored in the ground and then recovered via heat pumps in winter. The ground becomes a seasonal storage.
Norway’s first energy wall
Internationally, this technology is already well-established, but in Norway, we need reference projects. Fortunately, things are starting to happen. During the construction of Campus Ullevål — which will house NGI, NIVA, and CICERO, among others — Norway’s first “energy wall” is now being installed.
Here, the steel walls surrounding the excavation pit are equipped with more than 2,000 metres of piping designed to store and reuse around 250,000 kWh of heat annually from the clay beneath the building.
The potential is not limited to new construction. In Sauda, the smelter operated by Eramet is exploring the possibility of storing industrial surplus heat in the bedrock. By utilizing the ground as a seasonal store, energy that would otherwise be wasted can be recovered to help relieve the power grid during periods of peak demand.
Lasts for generations
The government highlights the need to reduce peak power demand in winter, but this is not clearly linked to existing solutions.
Once the foundation is built, the energy storage remains in place for generations to come. This is not about enthusiasm for a single technology, but about sound resource use and proper dimensioning of the power system.
Norway needs a larger toolbox. Some of the most robust solutions are already in the ground beneath the buildings we have yet to construct.
Google has demonstrated the potential. We have every prerequisite to do the same.
This op-ed, written by Thomas Langford, was published in Teknisk Ukeblad on 10 December 2025.
