Got Wind?

Answer: A and B.
The process that creates energy from the wind is relatively simple: Wind spins the blades on a turbine, which rotates a shaft with gears, which turn a generator that creates electricity. Wind power is one of the fastest growing sources of renewable energy, providing communities with a clean source of local power. The majority of wind farms in the United States are located on remote plains, where winds are stronger and more consistent than in densely populated areas. A number of wind farms have also been proposed for offshore sites, especially along the Eastern seaboard, where steady breezes make for ideal locations from a power-generating standpoint (although often not from a political one, given local opposition to the turbines).

Wind turbines mounted on city rooftops face greater challenges. Physical and technical difficulties such as wind shear, blockage from buildings, structural loads, noise, and vibration make it hard to deliver sufficient amounts of electricity to power a building. Small-scale installations, however, can be paired with photovoltaic panels and used to charge batteries for running small appliances and devices such as wireless routers. Improvements in turbine design hold hope for harnessing the wind more efficiently in urban areas.

Despite the still-limited use of wind power, federal and state governments recognize its potential. In New York State, residential home owners who install wind power systems qualify for the Energy Conservation Improvements Property Tax Exemption, which grants complete tax relief on purchased improvements made through renewable energy technologies. The state also grants a 15-year real property tax exemption on wind power systems (as well as solar and biomass technology). In addition, wind energy installations are eligible for the On-Site Small Wind Incentive Program offered through NYSERDA, as well as a 30% federal tax credit.

Although wind power has a long way to go before it can serve as a practical source of alternative energy for New York City buildings, a future with "windy city" turbines twirling from rooftops—minus the smoke from coal-fired furnaces below—is an exciting possibility.

Talkin' 'Bout Cogeneration

Answer: A and B.
Cogeneration, also known as distributed generation or combined heat and power, is a process that produces electricity and heat simultaneously. In a residential cogeneration system, a fuel-burning microturbine about the size of a refrigerator drives a generator to produce electrical power. Up to 90% of the heat produced in the process, which in a conventional power setup escapes as a wasted by-product, is instead captured and used to produce heat, hot water, or even cooling when sent through a steam absorption chiller.

A cogeneration system works in conjunction with the building's existing electrical and heating systems—it does not replace them. Although a microturbine won't supply enough electrical power for an entire large residential property, it can provide a steady supply of power throughout the year, thereby reducing the amount needed from the electric utility. Moreover, the electricity produced by the microturbine shaves the peak loads that buildings experience in the summer during heavy air conditioner use. Because of this supplemental capacity, Con Edison provides reduced electrical rates year round for buildings that run a cogeneration system. In addition, the system can be used as an emergency electrical backup during a power outage.

Similarly, a building with a cogeneration system still relies on its existing heating plant in the winter, but the microturbine supplies supplemental heat, reducing the plant's required output. In addition, a cogeneration system can be configured to heat the building's domestic hot water year round, drastically reducing boiler use in the summer. Depending on the property's hot water usage, the heat captured from the microturbine may even be sufficient to eliminate the need for the plant to fire up at all during the summer.

For large condominiums and cooperatives looking to reduce electrical and heating costs, it may be worth it to explore the potential savings that a cogeneration program can offer. No promises, however, that it will save you time or money on oral hygiene.

Embracing Your Inner Green

Answer: A and B.
Sustainable countertops and finishes are made from recycled materials such as paper, plastic, glass, aluminum, or reclaimed wood. The most environmentally friendly options do not contain petroleum byproducts and have little or no volatile organic compounds (VOC), substances that emit harmful fumes. Sustainable countertops and finishes come in a variety of colors and styles, and their surfaces are typically non-porous and resistant to stains, water, and heat. The best finishes are very dense and durable, which also make them an attractive choice for furniture, partitions, and panels. Kitchen countertops should be certified as "food safe" by the NSF, a public health and safety organization.

LEDs (light-emitting diodes) are solid-light bulbs that use semiconductor materials for their source of light. LED bulbs can last up to last up to more than 50,000 hours—two to four times longer than traditional fluorescent bulbs, five to 10 times longer than compact fluorescent lights (CFLs), and up to 50 times longer than incandescent bulbs. They also use far less electricity—three to seven watts per LED bulb compared to 20 to 35 watts for a fluorescent. Because they do not have a filament, LEDs are durable and hold up well to jarring and bumping, which could break a regular incandescent or fluorescent bulb. LEDs also do not build up heat, which cuts down on cooling costs, and they do not contain mercury as do other types of bulbs.

Until recently, LEDs were used primarily as single bulbs in instrument panels, electronic displays, and holiday lights. Because individual LED bulbs do not produce as bright a light as other types of bulbs, they are clustered by the dozens for larger lighting applications, such as flashlights, headlamps, and indoor lighting. LEDs now come with standard bases that fit common household light fixtures and are encased in diffuser lenses that spread the light in wider beams. Although the LED lighting is more expensive than traditional lighting, the cost is recouped over the bulbs' longer usage.

With the increasing selection of environmentally friendly finishes, lighting, and other interior design elements, you can now be both fashionable and green on the inside, no matter what your less-than-fashionably green neighbors are up to on the outside.

Sunny Side Up

Answer: A and B.
Solar thermal systems can generate either heat or domestic hot water for a building. The primary component is a solar collector, a flat or tube-shaped panel typically installed on the roof and directly exposed to the sun. The collector focuses the sun's energy to heat a fluid flowing through tubes in the collector. This fluid is piped to a heat exchanger, which transfers the energy to heat potable domestic water or heating hot water. As a result, solar thermal systems, which include pumps, storage tanks, and other devices, use less energy (gas, oil, electricity) to generate hot water, thus reducing operating costs.

In photovoltaic systems, energy from the sun is used to generate electricity. Photovoltaic collectors are typically flat plates arranged in an array on a building's roof. An inverter converts the photovoltaic's direct current into alternating current so it can be used for appliances and other devices. The converted current from the photovoltaic system is connected to the building's main electrical supply from the utility company. The building uses both sources of electricity; the amount of power drawn from the photovoltaic supply offsets the amount that would have come from the utility, a set-up known as net metering. The amount of savings through net metering depends on the building's location and the utility's specific policies and programs.

In addition to the savings from net metering, building owners with photovoltaic systems may be eligible to receive Solar Renewable Electrical Certificates (SRECs)—credits that can be sold to energy suppliers and utilities to help defray the cost of buying and installing photovoltaic equipment. Certification and prices for SRECs vary according to the state and market where they are sold.

Although solar power is still a little-used (but growing) technology in the New York City area, property owners may want to consider it as a viable source of renewable energy for their buildings. In the coming years we very well may see more and more city rooftops with solar panels—hopefully without eggs—sunny-side up.

The Heat Is On

Answer: A and B.
A heating plant's efficiency depends on how effectively steam or hot water is generated in the boiler and how well they are distributed throughout the building. Keeping the boiler properly maintained is the most critical part of that process.

In older steam and hot water systems, replacing an aging boiler can increase the system's overall efficiency and reduce fuel usage. Boiler maintenance between and during heating seasons can prolong the service life of equipment.

Maintenance items include cleaning heating surfaces (tubes, heat exchangers), checking valves, calibrating safety monitors, ensuring adequate airflow, and making certain the system isn't leaking. A heating contractor should perform tests on combustion efficiency and exhaust to determine if the system has suffered a decrease in performance from one season to the next. A maintenance log helps in planning repairs and replacements as the boiler approaches the end of its service life.

System balancing ensures that the boiler generates only the steam or hot water it needs to support the heating load in the building. It also ensures that all residents receive adequate heating by preventing the boiler from turning off prematurely and leaving portions of the building colder than others.

Balancing a steam system entails installing air vents on one-pipe systems (usually larger vents are installed at the top of the system), steam traps on two-pipe steam systems, and motorized steam valves on the main steam distribution in the cellar. Balancing in heating hot water systems requires devices called circuit setters—valves that adjust the flow of heating hot water so the optimal amounts reach units that need them most (e.g., apartments that don't face the sun).

As the winter season settles in and your building's boiler fires up, now's the time to focus on heating plant efficiency. With a well-maintained boiler and properly balanced system you won't have to burn through your property's operating budget—or stacks upon stacks of paper—to keep residents warm.

Keeping Your Cool

Answer: A and B.
Efficient cooling involves distributing cool, clean air to apartments and common areas. In a ventilation system that's not properly cleaned, the central cooling system has to push against dirt and blockages in the units and ductwork, hampering performance and shortening the life of cooling equipment. For room air conditioners, periodically removing and cleaning the filters improves airflow and air temperature. For systems with ductwork and supply air grilles, a duct-cleaning specialist uses a bristled vacuum to clean the interior of the ductwork. All components of an air conditioning system should be cleaned, including the inside of equipment. Ductwork cleaning reduces mold and mildew, removes harmful contaminants from the ventilation system, and improves overall cooling efficiency.

Balancing a ventilation system requires adjusting the airflow so it is at the designed rates throughout the building. For multifamily buildings with a rooftop air conditioning unit and ductwork feeding the hallways and apartments, balancing ensures that every unit receives the correct amount of air. In a building with a cooling system that's out of balance, residents on the higher floors (close to the main air conditioning unit) get far more airflow than those on the lower floors. Reducing the airflow to apartments or hallways at the top allows more air to flow to the units below, improving air distribution. Balancing improves comfort levels in a central system and ensures that the system operates efficiently.

Another smart cooling practice is selecting air conditioning equipment with the Energy Star label. The label is awarded to products that have a high energy efficiency ratio (EER) rating, from window air conditioners to chiller systems that cool entire buildings. More information on Energy Star products can be found at www.energystar.gov.

Keeping your building's cooling system clean and well-balanced will go a long way toward providing a comfortable, climate-controlled temperature for all residents. And you won't have to drag your building a long way to a much different climate to do so.

Energy Audits

Answer: A and B.
Energy audits provide property owners with an overview of how well their buildings' systems are performing and what can be done to improve their operating efficiency. Energy audits are also mandated under New York City's new Greener, Greater Buildings Plan, designed to make existing buildings more energy efficient.

An energy audit starts with a review of the building's utility bills to analyze the use of natural gas, fuel oil, and electricity over a continuous 12-month period within the last two years. The utility review looks at patterns of energy use, including peaks, valleys, trends, and any unusual signs that could indicate operational or usage abnormalities. The information is then compiled to determine the building's Energy Utilization Index (EUI), which is used as a baseline to compare against the EUI's of similar properties.

The utility review is followed by a visual survey of the building's major systems and conditions, including the building envelope (walls, windows, and doors); the roofing system and roof-level components; heating, ventilation, and air conditioning; electrical and lighting systems; elevators; and motors and pumps. During the walk-through of the building, the survey team records observable sources of energy loss or deficiencies that can be corrected with low- or no-cost repairs and installations, such as replacing incandescent bulbs with compact fluorescent lighting or insulating ductwork and piping.

Based on the utilities analysis and building survey, the audit firm prepares a written report that details their findings and provides a recommended scope of work for improving energy efficiency with estimates of potential costs and savings.

Energy audits figure prominently in New York City's recently enacted energy efficiency legislation, which includes four new local laws. One of them, Local Law 87/09, requires owners of buildings 50,000 square feet or larger to have an energy audit conducted every 10 years and identify and correct any deficiencies through repairs, adjustments, cleanings, and operational practices. An energy efficiency report, documenting the building's energy usage and operations, must then be filed with the city. (Here's a summary of the new legislation: New York City's Energy Efficiency Legislation.)

Although the word "audit" may conjure up an IRS inquisition, an energy audit can lead the way to lower energy costs for building owners and a healthier living environment for residents and tenants. And that's nothing to run—or jump—from.

Green on the Outside

Answer: A and B.
Many building products and materials, such as paint and paint strippers, coatings, cleaners, fuels, wood preservatives, pesticides, and miscellaneous solvents, contain volatile organic compounds, which are emitted as gases and can be harmful to people and the atmosphere. (The strong fumes are the VOCs.) Fortunately, more and more low- and no-VOC versions of these products are now available.

Conventional oil-based paints, for example, contain high-levels of VOCs and require toxic solvents to clean up, releasing even more VOCs into the air. As an alternative, latex paints, which use water as a solvent, provide good quality and durability and allow for an easier and a less-toxic cleanup.

Chemical facade cleaners, such as acid-based and alkali-based agents, leave hazardous materials in the run-off water after rinsing. Biodegradable gel-based, latex-based, and water-based products, however, do not contain harsh solvents or emit VOCs and can be used on most surfaces, including brick, concrete, metal, stone, and wood.

Traditional caulking agents are applied wet, and as they dry and cure, many release VOCs, formaldehyde, and other noxious products. Solvent-free caulking is available that emits minimal VOCs. These non-flammable, non-toxic products also resist shrinkage and discoloration.

Another way to keep your exterior restoration project green is to prevent the project's debris from ending up in a landfill. The construction documents for your building's upgrade project should specify that as much of the non-hazardous construction and demolition waste as possible (minimum of 50%) must be recycled or salvaged. This enables the recyclable resources to be re-manufactured, and it redirects other materials to sites where they can be reused. The debris—typically brick, concrete, metal, tiles, plastic, clean wood, glass, gypsum wallboard, insulation, carpet, and cardboard—is separated at the site or comingled on-site and then separated at an off-site facility.

Restoring your building's exterior can be done in a safe, environmentally friendly way that leaves the building looking beautiful but won't leave residents green around the gills—or anywhere else.

Taking the Floor

Answer: A and B.
Cork is harvested from the outer bark of the cork oak (Quercus suber) without killing the tree, and it regenerates in approximately 10 years. Cork's honeycomb cell structure, filled with air-like pockets, makes it lightweight, resilient, and a good insulator, reducing the transmission of sound, vibration, and heat. In addition, the natural give of a cork floor creates less grinding from foot traffic, leading to less wear and tear and easier maintenance.

Natural and recycled carpeting are also environmentally friendly flooring options. Carpets made from natural fibers, such as wool or jute, are constructed from renewable resources and are biodegradable after use. They also do not emit Volatile Organic Compounds (VOC), which can be harmful to breathe. Recycled carpeting is made from post-consumer products, such as plastic bottles (polyethylene terephthalate, or PET), which helps conserve resources and reduces the impact from manufacturing new materials. Many recycled carpets are also recyclable themselves and can be reused in other products or even back into carpets, lightening the load on landfills. Both natural-fiber and recycled carpeting dampen sound, a benefit in apartment buildings.

Bamboo is yet another green-friendly choice for flooring. It is a rapidly renewable resource, water-resistant, anti-bacterial, and very durable. Some bamboo flooring, however, uses formaldehyde-based adhesives, which contain high-levels of VOCs. In addition, most of the bamboo used in flooring is grown in the Hunan province of China, where some local forests and grasslands are being clear cut, turning them into a monoculture. If you decide to install bamboo floors, go with products that are FSC (Forest Stewardship Council) certified and do not contain formaldehyde additives. And be sure to keep plenty of extra bamboo shoots on hand for your always hungry panda.

It's Electric

Answer: A and B.
In a submetered building, each apartment has its own meter that tracks how much electricity is used in that unit. The submeters, usually located in the apartments themselves or in the building's electrical closet in the basement, are in addition to a master meter, which measures the buildings overall electrical usage. Buildings with only a master meter typically divide the electrical cost among shareholders as part of the monthly maintenance or common charges.

With submeters, however, residents pay for only the electricity they use, yet they can still purchase it at a cheaper bulk rate through the building rather than at a more expensive individual rate. (Submetered buildings often use a meter-reading company, which charges a small monthly fee per apartment.)

When residents pay for their own electricity, they begin to consume it more carefully. The New York State Energy and Research Development Authority (NYSERDA) estimates that residents use 15 to 30 percent less electricity after their buildings install submeters. That's good news for energy-conscious types, who no longer have to subsidize their energy gluttonous neighbors, who never met an electrical device they didn't like.

Windows Shopping

Answer: A and B.
High-performance windows feature thin metal or metallic oxide layers on the glass, which reduce the transfer of heat between the inside and outside. These nearly invisible low-e (low-emittance) coatings also help block ultraviolet light, which can cause interior furnishings to fade.

Energy-efficient windows also have double or triple panes with an inert gas (argon or krypton) in between them. The odorless, non-toxic gas serves as a buffer between the outer and inner panes, providing greater heat and sound insulation in addition to minimizing condensation and frost on the inside glass.

Other features of high-performance windows include improved frame materials, such as aluminum, wood composites, and fiberglass, as well as warm-edge spacers that keep the panes properly spaced, reducing heat flow and condensation.

Energy-efficient windows not only keep your apartment more comfortable; they also help save on heating and cooling costs. It's an open and shut case for your building-but only if your windows stay shut, not open.

How Green Is Your Roof?

Answer: A and B.
Green roofs offer many benefits that conventional roofs do not. For example, the layers of vegetation and soil protect roofing membranes from ultraviolet radiation, extending the life of the membranes up to twice as long as those on a conventional roof. The extra layers also provide additional insulation to the roof, reducing heating and cooling costs approximately 10% to 30% and allowing the building to use smaller HVAC equipment.

In addition, vegetation and soil layers reduce noise from traffic, planes, machinery, and other surrounding sounds for building residents, and the soil absorbs rain, reducing storm water runoff. Not only that: Green roofs add usable space and an aesthetically pleasing appearance to roofs, increasing a building's property value.

But as tempting as all that lush greenery is, please stay out of the rough with your neighbors by practicing your wedge shots on the golf course, not on the roof.

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