How multi-family dwellings can support the energy transition

Virtual power plants, microgrids and energy efficiency are some of the options for new and existing community housing.
Published: Thu 12 Sep 2019

Multi-family dwellings are a growing feature of today’s life, from the high-rise apartment buildings common in cities to the community complexes that comprise many modern building developments. With households a major user of energy – for example, accounting for 27% of final energy consumption in Europe in 2017 – their decarbonisation is key to meeting long-term carbon reduction targets.

However, in most if not all countries this will prove challenging due to issues such as differences in age, building styles and locations. Which is where multi-dwelling complexes come in and with appropriate planning, should become an important target to support utilities in the energy transition.

As examples, we offer two ongoing projects on different continents, one a new development, and the other a retrofit.

A community VPP in Salt Lake City

A new development offers a unique opportunity to build in from the outset smart and energy efficient features with energy providers a key partner in their delivery.

A community project under way near Salt Lake City has seen the local utility Rocky Mountain Power partner in a consortium with battery provider sonnen, solar manufacturer Auric Energy and property developer Wasatch Group to incorporate solar PV and storage and to operate it as a virtual power plant (VPP).

The 600-unit Soleil Lofts project in Herriman in southwest Salt Lake County comprises 5.3MW of solar to power the 26 buildings, covered parking and 100 electric vehicle charging stations, and 4.8MW/12MWh of battery capacity to provide utility demand response and local emergency backup power.

“Not only does Soleil Lofts all-electric community help improve air quality along the Wasatch Front in Utah, the partnership enables an innovative solution to provide low-cost utility services, not otherwise possible,” said Gary Hoogeveen, CEO of Rocky Mountain Power, at the project announcement.

Company spokesperson Spencer Hall told Engerati that in addition to the cost savings with leveraging the Soleil community partnership, the project creates opportunities in the areas of demand response, load shaping and rate design.

Moreover, as a first of its kind project for Rocky Mountain Power, numerous learnings and benefits are envisaged that will enable the company to advance and develop the use of solar and storage and microgrid-type solutions in the future.

“If proven successful, the project will provide a utility dispatch platform solution that can be utilised for all the sonnen batteries in our service territory,” says Hall. “Developers are proving the significant value in collaborating with the electrical utility to provide large-scale renewable power and storage options for customers. We intend to collaborate on similar projects with our customers.”

Rocky Mountain Power is a division of Berkshire Hathaway Energy and in addition to much of Utah its service territory covers communities across Idaho and Wyoming.

Full completion of the Soleil Lofts development is still a year away, but the first residents have started moving in and the project will formally launch in December.


Energy renovation in Île-de-France

Retrofitting new technologies into existing housing stock is a key route towards improved energy efficiency and decarbonisation of this sector, with cities a good place to start with their high residential density.

The Île-de-France region of France, which is the country’s most populous including Paris and its surrounds, has an ageing and energy inefficient housing stock with more than a million multi-ownerships in the three lowest energy categories. The potential for improved energy efficiency is considerable, but barriers are the complexity and costs with a lack of adequate organisation and financing.

Île-de-France Energies, established as a local public-private company Energies POSIT’IF in 2013, has focussed on developing innovative financial options to address these issues. Its latest, via a €100 million loan from the European Investment Bank, is a third party financing scheme for all inclusive energy renovation of these multi-ownership buildings. 

The company states that in principle, energy savings are mobilised to finance retrofit works. Practically however, it was found necessary to provide support on both the technical and financial aspects of the renovation. With third party financing, further financing is available to co-owners with the additional loan repayment essentially offset by the energy savings.

Île-de-France Energies offers the third-party finance as a group loan with opt-in, i.e. each co-owner has the choice of whether or not to join. The loan can finance works on common parts of the building such as wall or roof insulation or collective heating, and specific private parts in the ‘common interest’ such as windows.

“The advance of the project solves many complex situations for families and the group loan we propose with third-party financing provides a quick and efficient solution to the financing of works,” says Benjamin Chkroun, Chairman of the Supervisory Board of Île-de-France Energies and Regional Advisor of Île-de-France in a statement.

Under French law the entire housing stock must be renovated to low energy consumption standards by 2050 with a target of 500,000 renovations per year.

Île-de-France Energies has renovated over 3,100 apartments achieving average energy savings of 50%.