UK Power Networks has handed over half of its former electricity substation at Bankside to Tate Modern to allow the expansion of the gallery.
It is the culmination of a six-year £60 million substation refurbishment in the building alongside the modern art gallery's Turbine Hall.
New electrical equipment has been installed inside the refurbished substation and has been connected to London's existing electricity distribution network.
Modernising the substation has released more than 1,000 square metres of space for the expansion of Tate Modern on the southern side of the building. The rebuilt substation has halved in size, enabling the art gallery to grow.
As an additional benefit, heat emitted by the six electricity transformers in the new substation will be captured and used for heating and hot water in the new building. At full capacity, the system will have the potential to provide about 600kW of heat.
"Our customers rely on our electricity infrastructure to go about their daily lives and our investment in this site will help ensure the continued reliability of electricity supplies for a large area of London," says Basil Scarsella, chief executive of UK Power Networks.
"This upgrade has halved our substation footprint, allowing the expansion and enhancement of Tate Modern in the large area which has been vacated.
"We are proud that an innovative waste heat recovery system in our new substation will eventually be turning heat from our electricity transformers into hot water and heat for the gallery. It will demonstrate energy efficiency on a grand scale."
An intricate maze of pipes has been fitted in the substation to capture and recycle heat from the substation's transformers to use in the adjoining gallery.
"The handover of the substation is a crucial step in the Tate Modern project and takes us to the next stage of building work," explains Alex Beard, deputy director of Tate.
"The handover is the culmination of a five year partnership and could not have been achieved without UK Power Networks' commitment and determination and the vital financial support of the London Development Agency.
"Being close to the community has always been important to Tate Modern. This next stage is one that will lead to a new north/south route from the Millennium Bridge through the existing Tate Modern to Southwark."