In New York, 80% of carbon emissions are caused by the energy used in buildings, and the single largest owner of buildings in the city is the council, which has set itself a carbon reduction target of 30% in the next seven years. To acheive this high-profile reduction, the city council has agreed a wide-ranging programme of works called ‘PlaNYC‘ and the city’s ‘Greener, Greater Buildings Plan‘ is a large part of this programme.

Having lower energy bills in buildings makes economic sense as well as environmental sense. The beauty of the New York Greener, Greater Buildings Plan is that it includes a refurbishment programme of works which is income-positive after three years, and balance-positive after five years, where the income has fully paid for all the works to date.

Already the city council has measured and benchmarked 2,790 buildings, which includes every city-owned building over 10,000 square feet. The measures include electricity, gas, steam and fuel oil; as well as the building type, year of construction, number of workers and total floorspace.

As Michael R. Bloomberg, City Mayor said, “You can’t manage what you don’t measure, and benchmarking the City’s buildings lets us determine where energy costs can be reduced”.

Leadership

It is also about leadership, where he added, “As the largest building owner in the country’s largest city, we can serve as a model for all building owners”. Commissioner Martha K. Hirst for the Citywide Administrative Services said, “As we continue to target buildings for comprehensive energy audits, new retrofit projects, and simple improvements in routine maintenance, this [benchmarking] data will show us where we can achieve the greatest gains for every dollar spent”.

By May this year the council’s Division of Energy Management has completed 84 retrofit projects and has 145 planned projects, due to save over 87,000 tonnes of greenhouse gases.

One of the key retrofit projects is to cool one million square feet of rooftop space this year, announced last year with Al Gore, simply by applying a reflective white coating to roofs so that the summertime air conditioning load in the city is reduced. This project also includes the buildings of City University NY and the New York LaGuardia Community College. The Cool Roofs project includes corporations, city agencies, nonprofit organisations and citizen volunteers.

NYPD Blue – going Green via White

Already cooled with a white roof is the NYPD’s 40th Precinct House in the Bronx – NYPD Blue has truly got to green via white.

For new buildings, the city’s 2008 Building Code requires most new roofs to have a reflective coating on at least 75% of the roof area. A cool roof absorbs 80% less heat than a traditional dark roof, and can lower the roof temperature by up to 60F and lower indoor temperatures by between 10F and 20F on hot days. As well as reducing air conditioning costs (up to 50% for a single-storey building) the cool roof also extends the lifespan of the roof by five to ten years because of the lower heat stresses.

The NY Cool Roofs project is being monitored by Columbia University’s Centre for Climate Systems Research, and they are developing an online dashboard so that the public can see real-time performance data. Citizen volunteers as well as building owners can call the city council switchboard for details on how to give back by working to reduce greenhouse emissions.

In July this year, New York City Council added to its portfolio of works for greenhouse gas reductions from buildings by announcing a new energy code for the city, which extends the energy efficiency standards for buildings to a wider coverage for the city compared with the equivalent state codes. Under the state code, retrofits which apply to less than 50% of a building are exempt from many of the energy efficiency requirements, but the city’s tougher code will now apply to a further 50,000 building retrofits each year, based on last year’s figures.

Lessons for Britain

What does this mean for councils this side of the ocean? In recent years British local authorities have been allowed to undertake prudential borrowing.  For example, Kirklees Metropolitan Borough Council adopted a five-year capital budget in 2009 with £218m of prudential borrowing to fund projects such as the Warmzone Plus project. According to the council this “will significantly reduce the carbon emissions of homes in Kirklees, in funding alternative energy uses in Council buildings and by allocating resources to support a District Heating initiative”.

But more recent statements by HM Treasury have cast a shadow on the prudential borrowing powers of local authorities. It remains to be seen whether the new Government’s localism agenda will extend to self-funded green retrofit programmes. They can work in New York, but can we do the same here in Manchester?

First published: 02 August 2010