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Part IV: Energy Efficient Buildings



Heating, cooling, lighting and powering buildings efficiently is easiest with new green buildings, but efficiency must also be increased for the larger stock of existing buildings.  


  • increase mandates and incentives for energy efficiency retrofits

  • mandate energy efficiency standards for equipment

  • encourage solar heating systems

  • design buildings for maximum cost-efficient energy performance

  • reduce unnecessary outdoor lighting

  • discourage acceptance of relentless growth in personal electricity consumption

Buildings account for 71% of electricity and 39% of all energy use in the US.  In NYC, 79% of carbon emissions come from its 750,000 residential, commercial and government buildings, mostly from the power plants that supply them with electricity. [1] Over 20% comes from transportation. [2] 

Densely packed apartment buildings are inherently more energy efficient than individual houses.  PlaNYC relies on that for much of its projected carbon emission reductions, estimating the energy savings from housing 900,000 new residents within the City instead of housing them in less efficient sprawling communities. The plan aims to reduce energy use by improving efficiency of existing buildings, setting higher efficiency standards for new buildings and appliances, and greening building and energy codes. [3] 

The City’s Local Law 86 will ensure that many new buildings built or owned by the City will meet higher standards of energy efficiency, [4] but the vast majority of existing buildings chronically waste energy.  Although many energy efficiency retrofits can pay for themselves in a few years through energy savings, they are still comparatively rare.  Our electricity use is growing rapidly.  PlaNYC says that between 2000 and 2005, NYC’s greenhouse gas emissions increased almost 5%.

Almost half of that growth can be traced to the rising energy consumption of every New Yorker in the form of cell phones, computers, and air conditioners; the rest is due to new construction.  If these trends continue, by 2030, the city’s CO2 production will increase 27% over our 2005 emissions. [5]

Given that gap, there must be still more ambitious incentives and mandates for energy use reductions.  Urban Agenda recommends requiring that cost-effective residential energy improvements be made at point of sale or significant renovation, as well as disclosure of energy costs at point of sale.  NY Climate Rescue recommended:

  • requiring energy retrofits for owners of all buildings over 10,000 square feet, with incentives for owners of smaller buildings.

  • providing financial incentives for landlords and tenants to work together to improve energy efficiency and install renewable power, following thePay as You Save initiative.

  • increasing lightbulb efficiency and phasing out conventional incandescent light bulbs, as will Australia, the European Union countries, and China, maker of 70% of the world’s light bulbs [6]

  • banning sale and installation of non-EPA EnergyStar rated air conditioners and refrigerators. 

Also, improving building energy efficiency presents one of the most promising local opportunities for developing good jobs that cannot be outsourced.  AnUrban Agenda report provides an excellent overview of New York’s existing energy efficiency sector.  [7] 

1. Energy audits and efficiency upgrades


The first step to greening a building is definitely not installing solar panels on the roof.  Building owners should start with an energy audit to review lighting, heating, ventilation and air conditioning systems, and then carry out recommended repairs and upgrades, install insulation and plug leaks that waste energy by losing heated or cooled air.  Ways of saving energy in buildings are laid out in the Feasibility Study for Greening a Block.  This proposal to bring state-of-the-art energy efficiency improvements to a concentrated area in the Lower East Side is expected to cut both heating fuel and electricity use an average of 30%. [8] Unfortunately, the project has been mired in red tape for years.

Guidance and resources for energy efficiency in buildings is available from GreenHomeNYC, New York Energy $mart Communities, and Apollo Alliance. [9] The Association for Energy Affordability, NYC College of Technology, and NYC Department of Housing Preservation and Development offer courses. [10]


Reducing electricity consumption.

First, change lightbulbs from incandescent to fluorescent, replace older fluorescent T12 or T10 tubes with T5s, and then upgrade to energy efficient appliances.  Next, calculate the energy needs of the space to size the most efficient pumps, fans and elevators.  Photocells, occupancy sensors, daylight sensors and dimmable ballasts for lighting can save even more energy. Turning off appliances not in use, including computers, and putting appliances on power strips that can be turned off when not in use can also save energy. 

Tuning boilers and heating systems. 

While becoming more comfortable and easy to adjust to resident needs, most NYC residential buildings can save 40% of their heating fuel through proper configuration and tuning of their existing heating system. [11] Boiler maintenance training for building owners, managers, superintendents and porters is a great investment.  A typical 15 to 30 unit walk-up building on the Lower East Side can save 200 to 300 gallons of fuel per apartment per year. [12] 

2. Solar heating systems

Rooftop solar thermal systems can supply 25 to 55% of a small residential building’s water heating needs and some of its heating load.  They convert about 70% of solar energy into heat, compared to the 18 to 19% efficiency of solar panels, so slight roof shading is less of a problem.  Residential solar water heating systems cost about 10 times as much as established but less efficient electric and natural gas water heaters, pay for themselves in 4 to 8 years through fuel savings, and last 15 to 40 years.  For solar thermal retrofits to become standard practice on flat-roofed City buildings, overall building and labor costs, as well as burdensome building regulations, must be reduced. [13] At this time, most solar water heating systems in the U.S. are used to heat swimming pools. [14] All new homes built in Germany after 2008 will be required to install renewable energy heating systems, and after 2010 the remaining houses will have to add them as retrofits. [15] 

3. Efficient design 

Architecture 2030 has challenged architects and builders to halve greenhouse gas emissions and energy consumption in designs for new buildings and major renovations, with all new buildings carbon neutral by 2030 – that is, requiring no fossil fuels to operate. [16] This sounds ambitious, but NYC architect and building science advocate Chris Benedict currently achieves energy savings of around 50% in her renovations, and her new buildings are 85% more fuel efficient for heat and hot water than typical buildings of the same size – at no extra cost. [17]

The Leadership in Energy and Environmental Design green building rating system (LEED) ranks buildings on a number of factors. [18] Industry critics say LEED doesn’t adequately prioritize energy performance, and a costly, bureaucratic process contributes to the very small number of buildings that have actually been LEED certified. [19]

Building science practitioners focus mainly on performance, using hyper-efficient design to sharply reduce energy use at about the cost of regular building [20] Through innovative architectural design and mechanical engineering, buildings of all sizes can be made more energy efficient, safe, healthy, and comfortable.  The best results come from a new building where everything is done right at the outset; a small remodeling job on an inefficient building may do little good.  An existing single-family house may benefit most from improvements to the building enclosure such as air sealing, additional insulation, sun shading, or building a completely new air barrier.  The most economical strategies for larger buildings, whether existing or new, are ensuring correct mechanical system design, overall system controls, and providing room-by-room temperature control for heating and cooling.  By doing all the work right at the start, energy use in four new apartment buildings on the Lower East Side is only 15% of average use for heat and hot water and 50% for common area electricity. [21]





1. NYC Dept. of Buildings,

2. “Cleaning Up New York’s Buildings,” Gotham Gazette, Oct. 15, 2007,; "Emissions Data," PlaNYC, 2030,

3. PlaNYC 2030, p. 134,; NYC Dept. of Buildings,;

4. NYC Dept. of Design & Construction,  

5. PlaNYC, p. 135,

6. “China to phase out incandescent light bulbs,” Environmental Leader, Oct. 3, 2007,;NY Climate Rescue, April 2007; Responses to PlaNYC, Office of the Public Advocate; PAYSAmerica,;

7. “Growing Green Collar Jobs: Energy Efficiency,” Urban Agenda, 2007,

8. Greening A Block,

9. GreenHomeNYC,; NYSERDA,; “New Energy for Cities:  Energy Saving and Job Creation Policies for Local Governments,”Apollo Alliance,

10. The Association for Energy Affordability,; NYC College of Technology,; NYC Dept. of Housing Preservation and Development,

11. "Notes on oil conservation," Superintendents Technical Association,;

12. "Feasibility Study," Greening A Block,

13. Personal communication, solar energy designer and installer Richard Klein, Quixotic Sytems, Inc.,

14. “American Energy: The Renewable Path to Energy Security,” Worldwatch Institute / Center for American Progress, p. 31, Sept. 2006,

15. “Germany to Require Renewables for New Homes in 2009,” Renewable Energy Access, December 10, 2007,

16. Architecture2030,

17 . “Cleaning up New York’s Buildings,” Gotham Gazette, Oct. 15, 2007,; 
“Third Street:  on one block in New York City, good design and readily-available materials trump fancy technology,” Henry Gifford, Home Energy, Sept. 2005.

18 . US Green Building Council,

19 . “What’s Wrong with LEED?,” Steven Del Percio, The Next American City, Spring 2007,  

20. "Section 1: the building connection," Building Science. 

21. Personal communication, architect Chris Benedict, GreenHome Guide,

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