Detailed energy planning saves money and Co2

Green transition 10 May 2017 Isidore McCormack Jens Ole Hansen

A growing number of US cities are striving to lower their carbon footprints. District heating with flexible use of energy sources is a cost-efficient way of achieving this. An energy technology professor sees a huge potential.

8 min

Low-carbon organisations and networks like The Carbon Neutral Cities Alliance (CNCA), Compact of Mayors and C40 continue to attract new members and partners, also in the USA. One of the most active cities in the field, Cambridge in Massachusetts, has chosen Ramboll to prepare a masterplan to significantly decarbonise its energy supply.

Green energy city planning is increasingly a competitive parameter for US cities attempting to attract the best and most progressive students, academics and businesses. Cambridge is home to two of the world’s most prestigious universities, Harvard and the Massachusetts Institute of Technology (MIT), both of which have made a low-carbon future a priority.

"The state of Massachusetts has ambitious carbon reduction targets, as do a lot of US cities and colleges, which creates a competitive drive between sustainability managers in the respective locations to get to carbon neutrality first," says Isidore McCormack, Project Manager at Ramboll Energy.

Copenhagen as example 

He explains that due to e.g. regulations USA was slower than Europe to get into carbon reduction energy planning projects and the integral role district heating can play when a city implements its carbon neutrality strategy.

This provides an opportunity for us, as we have Copenhagen and other cities as tangible examples of our energy masterplanning capability.

Energy planner Seth Federspiel from the city of Cambridge confirms this:

“We selected Ramboll to conduct the Low Carbon Energy Supply Study because of Ramboll’s deep technical experience in energy systems planning, particularly at the district scale, as well as the company’s willingness to consider innovative opportunities for meeting Cambridge’s goal to become a carbon-neutral city.”

Campus and university focus

Establishing district heating in the USA is usually more complicated than in Europe. The widespread private ownership and lack of regulation for hot water district energy pipes make it difficult, for example, to lay pipes in the roads. Ramboll’s main strategy for exporting district energy services to the USA is therefore to focus primarily on private campuses and universities, which are centrally owned as in Europe.

"But in our experience, if a US city really wants district heating, it too can be integrated into the city’s urban planning, climate resiliency planning and energy planning in a holistic and cost-efficient way that benefits citizens," Isidore McCormack says.

A flexible energy system

Cambridge’s goal is to be totally carbon neutral in 2050 and to have zero emissions from buildings by 2040. Today, the city’s heating and electricity primarily come from oil and gas. So, Ramboll is investigating a potential lever that involves converting some of this fossil fuel supply into solar or wind energy imported from outside the city. Sources could include, for example, the offshore wind farms, whose potential the state of Massachusetts is currently studying and which may be a viable solution in low-density areas.

Even without changing the energy source, however, massive savings on CO2 – and money – are in the pipeline. European-style district energy based on hot water can save up to 30% in operational costs compared to traditional US district heating systems, which are steam-based and fairly inefficient.

With the right planning, the hot-water-based system is flexible, so the energy source can be changed at a later time.

The most sustainable solution

To date, our local subcontractor, Vanderweil Engineers, has assisted with collecting data on Cambridge’s present energy use. The next project development stage is to identify potential scenarios for the city that are energy efficient and sustainable from the environmental, social and economic perspectives. This will result in an energy road map enabling the city to achieve its objective of decarbonising its energy supply.

Ramboll has expanded its Boston office to accommodate the growing demand for energy planning. That could prove a very wise move, according to external experts:

“The market share for district heating in North America is only a few per cent. So the potential market is huge,” Sven Werner, Professor of Energy Technology at Halmstad University in Sweden and a world-leading expert on district heating, points out.

Apart from Cambridge, Ramboll is participating in district energy projects in the urban areas of St Paul in Minnesota, Bridgeport in Connecticut and Guelph in Ontario, Canada. Ramboll also has projects at MIT, Dartmouth College in New Hampshire, Wesleyan University in Connecticut, and Sheridan College in Canada.


Written by Michael Rothenborg