energy

Solar farms in space could be renewable energy’s next frontier

Posted on by abrahamwien18
space-based-solar-array-concept

Space-based solar power is seen as a uniquely reliable source of renewable energy. NASA / Artemis Innovation Management Solutions LLC

China wants to put a solar power station in orbit by 2050 and is building a test facility to find the best way to send power to the ground.

By Denise Chow and Alyssa Newcomb
View the original article here.

As the green enery revolution accelerates, solar farms have become a familiar sight across the nation and around the world. But China is taking solar power to a whole new level. The nation has announced plans to put a solar power station in orbit by 2050, a feat that would make it the first nation to harness the sun’s energy in space and beam it to Earth.

Since the sun always shines in space, space-based solar power is seen as a uniquely reliable source of renewable energy.

“You don’t have to deal with the day and night cycle, and you don’t have to deal with clouds or seasons, so you end up having eight to nine times more power available to you,” said Ali Hajimiri, a professor of electrical engineering at the California Institute of Technology and director of the university’s Space Solar Power Project.

Of course, developing the hardware needed to capture and transmit the solar power, and launching the system into space, will be difficult and costly. But China is moving forward: The nation is building a test facility in the southwestern city of Chongqing to determine the best way to transmit solar power from orbit to the ground, the China Daily reported.

REVISITING AN OLD IDEA

The idea of using space-based solar power as a reliable source of renewable energy isn’t new. It emerged in the 1970s, but research stalled largely because the technological demands were

thought to be too complex. But with advances in wireless transmission and improvements in the design and efficiency of photovoltaic cells, that seems to be changing.

“We’re seeing a bit of a resurgence now, and it’s probably because the ability to make this happen is there, thanks to new technologies,” said John Mankins, a physicist who spearheaded NASA efforts in the field in the 1990s before the space agency abandoned the research.

Population growth may be another factor driving the renewed interest in space-based solar power, according to Mankins. With the world population expected to swell to 9 billion by 2050, experts say it could become a key way to meet global energy demands — particularly in Japan, northern Europe and other parts of the world that aren’t especially sunny.

“If you look at the next 50 years, the demand for energy is stupendous,” he said. “If you can harvest sunlight up where the sun is always shining and deliver it with essentially no interruptions to Earth — and you can do all that at an affordable price — you win.”

MAKING IT A REALITY

Details of China’s plans have not been made public, but Mankins says one way to harness solar power in space would be to launch tens of thousands of “solar satellites” that would link up to form an enormous cone-shaped structure that orbits about 22,000 miles above Earth.

The swarming satellites would be covered with the photovoltaic panels needed to convert sunlight into electricity, which would be converted into microwaves and beamed wirelessly to

ground-based receivers — giant wire nets measuring up to four miles across. These could be installed over lakes or across deserts or farmland.

Mankins estimates that such a solar facility could generate a steady flow of 2,000 gigawatts of power. The largest terrestrial solar farms generate only about 1.8 gigawatts.

If that sounds promising, experts caution that there are still plenty of hurdles that must be overcome — including finding a way to reduce the weight of the solar panels.

“State-of-the-art photovoltaics are now maybe 30 percent efficient,” said Terry Gdoutos, a Caltech scientist who works with Hajimiri on the space-based solar research “The biggest challenge is bringing the mass down without sacrificing efficiency.”

For its part, the Caltech team recently built a pair of ultralight photovoltaic tile prototypes and showed that they can collect and wirelessly transmit 10 gigahertz of power. Gdoutos said the prototypes successfully performed all the functions that real solar satellites would need to do in space, and that he and his colleagues are now exploring ways to further reduce the weight of the tiles.

THE ROAD AHEAD

China hasn’t revealed how much it’s spending to develop its solar power stations. Mankins said that even a small-scale test to demonstrate the various technologies would likely cost at least $150 million, adding that the swarming solar satellites he envisions would cost about $10 billion apiece.

Despite its exorbitant price tag, Mankins remains a staunch advocate of space-based solar power.

“Ground-based solar is a wonderful thing, and we’ll always have ground-based solar,” he said. “For a lot of locations, rooftop solar is fabulous, but a lot of the world is not like Arizona. Millions of people live where large, ground-based solar arrays are not economical.”

Mankins hailed recent developments in the field and said he is keen to follow China’s new initiative. “The interest from China has been really striking,” he said. “Fifteen years ago, they were completely nonexistent in this community. Now, they are taking a strong leadership position.”

EMERALD SKYLINE PARTNERS WITH BLUE PILLAR TO PROVIDE THE ENERGY NETWORK OF THINGS POWERED BY AURORA

Posted on by abrahamwien18

South Florida-based Emerald Skyline brings 21st Century technology to energy management.

“Over 75% of businesses say that Internet of Things (IoT) is critical to their future success, and nearly half of adopters are using IoT to support large-scale business transformation.” Vodafone IoT Barometer 2016

January 10, 2017 from Emerald Skyline Corporation (www.emeraldskyline.com)

BOCA RATON, FL, January 10, 2017 – FOR IMMEDIATE RELEASE

Today, Emerald Skyline announced that it has partnered with Blue Pillar, Inc. to provide the Energy Network of Things powered by Aurora for hospitals, office buildings, retail centers, industrial and municipal facilities. Together, we’re transforming the energy industry by developing intelligent energy management solutions to help facility managers achieve their energy resiliency, efficiency and sustainability goals.

Blue Pillar connects any energy “thing” (i.e., any asset that consumes, switches or measures electricity — including meters (water, gas and electric), generators, fuel tanks, automatic transfer switches, chillers, boilers, HVAC control panels, CHP, solar panels, EV chargers and just about any other intelligent mechanical equipment you can think of — into our Energy Network of Things platform.
Blue Pillar’s Aurora Energy Network of Things™ platform has an architecture that is open at the device and application layer, so it is perfectly positioned to solve the energy management data crisis. In addition to being open and providing ubiquitous connectivity, we also offer dozens of energy management applications the same way that a calculator or calendar app would be offered on your Apple or Android phone.

“As a sustainability and resiliency consulting and LEED project management firm, this partnership enables us to provide the industry’s most flexible platform for connecting and managing energy devices,” reports Abraham Wien, LEED AP O+M, Director of Architecture & Environmental Design for Emerald Skyline. “We are always looking for ways to provide superior products and services to meet our clients sustainability and resiliency needs and Blue Pillar is an IoT provider that we are proud to offer to the market.”

For nearly a decade, Blue Pillar has connected thousands of energy assets at a wide variety of deployment sites from hospitals and energy service providers to data centers and higher education campuses enabling them to work 75% faster and realize 30% more affordability.

To find out more information about the employment of the Blue Pillar IoT for building energy systems in your building or facility and unleash the power of real-time data that strengthens your infrastructure and improves not only your efficiency but provides opportunities for differentiation and even new revenue sources while providing for a greener tomorrow, please contact Abraham Wien at [email protected] or call us 305.424.8704.

The Importance of an Energy Assessment for Commercial Buildings

Posted on by abrahamwien18

By John Losey, Owner and Founder The BP Group, Energy Manager Today, 9/1/2016

View the original article here.

Building owners and property managers that take on the responsibility of limiting energy consumption can be looked at as environmental leaders. While energy management adds extra tasks to everyday lists, the benefits outweigh the time and money spent, which is usually returned in savings.

There are numerous areas to take into consideration when it comes to commercial buildings, and being that commercial buildings are generally large, the impact can be large as well. These areas include the HVAC system, chillers, windows, lighting, electrical equipment, and any other factors that may be contributing to the building’s energy consumption.

While there are various ways to be involved with bettering the environment outside of where you live and work, starting in a place that you occupy everyday has the potential of having long term results if the actions are carried through as often as you’re there.

Consider creating an outlined approach for managing the building’s energy with these areas in mind:

Identify Sustainable Alternatives Where Energy is Being Used:

  • Are there upgraded, energy-efficient versions of the equipment you can be using instead?
  • Could you use different settings on the equipment?

Assess the Purpose of Every Area:

  • Is the lighting being utilized in every room?
  • Is the size of the HVAC system an adequate fit for the building and its purpose?

Evaluate Maintenance Plans:

  • How frequent are the utilities maintained?
  • Do the maintenance technicians practice with energy efficiency in mind?

Look for Possible Areas of Energy Loss:

  • Are the building’s windows sealed properly?
  • Is the equipment too old for efficient functioning?

These are questions you should ask yourself if you’re trying to assess energy consumption and find that alternative route to save not only energy, but money as well.

After addressing these questions, you may find yourself planning to make some changes. Here is the information you should know for doing so:

Energy Efficient Equipment: Whether it’s the HVAC system, the utility lighting or the other various appliances being used in the building, there are energy-efficient options to consider. This includes ones with ENERGY STAR ratings, which match the standards set by the government.

Settings & Thermostats: Just by being knowledgeable about specific settings and the different types of available thermostats, you can be saving a substantial amount of energy. Depending on the type of building and the function(s) of the building, settings can be applied to use less energy in an area that doesn’t need it. The same idea goes for thermostats. Programmable thermostats allow for precise regulation of energy consumption. This means making sure the temperatures aren’t set too high or too low when the building or part of a building isn’t in use. Programmable thermostats keep the location comfortable when needed, but help save energy when it’s not.

Lighting: It’s better to be the building that turns its lights off when it isn’t being used, than a building that keeps them on 24/7. It’s also important to consider energy-saving types, such as LED or solar. With these kinds, you can also invest in timers and dimmers.

HVAC Size: According to ENERGY STAR, “at least 25% of all rooftop HVAC units are oversized, resulting in increased energy costs and equipment wear.” Determining what size HVAC system the building needs is a job for a professional technician, and it’s an important part of the overall building assessment.

Maintenance: Building maintenance is not only important for saving energy and money, it’s important for the building’s health and those occupying it. This includes electrical, HVAC, plumbing, etc. While there are tasks you can manage on your own, there are specific tasks that are recommended for the hands of a professional technician. Whatever the area, it’s important to have maintenance scheduled. Having a definite schedule helps to prevent sudden issues, which prevents sudden energy loss as well.

Technicians: Certain companies know the importance of offering energy-efficient services. This means that they practice in ways that are beneficial for the environment. Research the companies in your area and look for the ways they’re working to save energy and you money. This is an important quality, and more companies are beginning to realize that.

Windows, Replacements & Other Areas of Loss: Other ways to assess energy is by looking into the not so obvious. This includes windows, old systems that don’t show signs of stress until it’s too late, and too many running appliances and pieces of equipment causing heat. If windows aren’t sealed properly, especially in summer and winter, your HVAC system may be working harder than it has to in order to reach the desired temperature. Leaks of hot or cold air will cause this. Another concern are systems that don’t show signs of stress. If the system is old, it’s definitely recommended to have it maintained, even if you think otherwise. The inside has moving parts that may be working very hard to keep it running, and the machine giving out might be the first sign if you wait too long. Lastly, there may be too much heat. Too many heat producing appliances or pieces of equipment may cause the air conditioner to work harder, similar to an open window on a hot summer day.

Commercial buildings don’t function alone, they need the help of energy, and all building owners and property managers can help conserve it.

John Losey is the owner and founder of The BP Group, a leader in Commercial HVAC Services

Sustainable Building Design

Posted on by abrahamwien18

Julie
By Julie Lundin, LEED AP ID+C,
Principal, Emerald Skyline Corporation

Our project in Boca Raton is being designed to become a LEED certified building. The U.S. Green Building Council’s (USGBC) Leadership in Energy and Environmental Design (LEED) green certification system is a tool for evaluating and measuring achievements in sustainable design. LEED consists of a set of perquisites and credits with specific requirements for obtaining points in order for a building to become LEED certified.

Many people are not familiar with the concept of sustainable design and how it relates to building construction and ongoing building operations. The built environment impacts our natural environment, our society and our economy. This concept is often referred to as the 3 P’s, people, planet and pocketbook. Sustainable design attempts to balance the needs of these areas by integrating design solutions.

EPA

EPA 2004

The main objectives of sustainable design are to reduce or avoid depletion of natural resources such as energy, water, and raw materials; prevent environmental damage caused by buildings and their infrastructure; and create livable, comfortable and healthy interior environments.

Sustainable design does not just apply to new construction; retrofitting of existing buildings should be an option and can be more cost-effective than building a new facility. With our project, we opted to retrofit as well as reposition an existing building rather than allowing further decay of the property or demolishing it and building new. My future posts will focus on specific details and products that we will utilize in our sustainable design process.

While the definition of sustainable building design continues to evolve, according to the Whole Building Design Group (WBDG) Sustainable Committee there are six fundamental principles that persist. References to some of our sustainable design solutions that will be written in upcoming posts are included below in the fundamental principles.

 

Optimize Site Potential

Creating sustainable buildings starts with proper site selection, including the reuse or rehabilitation of existing buildings.

  • We chose a contaminated site and remediated the property.
  • The project is an abandoned auto body garage that will be repurposed rather than demolished.

Location, orientation, and landscaping of a building affect ecosystems, transportation methods, and energy use.

  • A south facing orientation will enable us to harness solar energy and utilize the sun for daylighting within the structure.
  • Proximity to major bus and train lines provides alternative transportation.
  • The use of native plants and rainwater collection

Optimize Energy Use

It is essential to find ways to reduce energy load, increase efficiency, and maximize the use of renewable energy resources.

  • Solar energy via solar panels
  • LED lighting
  • Daylight Harvesting
  • Energy efficient windows, appliances, and HVAC

Protect and Conserve Water

Fresh water is an increasingly scarce resource; a sustainable building should use water efficiently, and reuse or recycle water for on-site use.

  • Cistern and water collection
  • Low flow toilets, sinks, and appliances
  • Grey water use where allowed

Optimize Building Space and Material Use

Available resources are stressed to due demands for additional goods and services. A sustainable building is designed and operated to use and reuse materials, environmentally preferable materials have a reduced effect on human health and the environment.

  • Shared uses for small building space
  • Low VOC paints, sealants and adhesives
  • Use of reclaimed wood

Enhance Indoor Environmental Quality (IEQ)

The IEQ of a building has a significant impact on occupant health, comfort, and productivity. A sustainable building maximizes daylighting, has appropriate ventilation, moisture control, optimizes acoustic performance, and avoids the use of materials with high-VOC emissions.

  • Low VOC paints, sealants and adhesives
  • Flush out building before occupancy
  • Thermal Comfort Control
  • Provide quality views

Optimize Operational and Maintenance Practices

Encourage optimal operations and maintenance systems during the design and development phases, specify materials and systems that simplify and reduce maintenance requirements; require less water, energy and toxic chemicals. Include meters to track sustainability initiatives, reductions in energy and water use and waste generation.

  • Energy and water metering
  • Recycling Waste Plan
  • Building Envelope Commissioning

 

Utilizing a sustainable design philosophy encourages decisions at each phase of the design process that will reduce negative impacts on the environment and the health of the occupants, without compromising the bottom line. It is an integrated, holistic approach that encourages the balance of people, planet and pocketbook. An integrated approach of sustainable design should positively impact all phases of a building, including design, construction and operation.

Sources:

http://www.wbdg.org/design/sustainable.php

 http://www.gsa.gov/portal/content/104462

How you can help make Florida the Sunshine State again

Posted on by abrahamwien18

Julie

By Julie Lundin, LEED-AP ID+C,
Principal, Emerald Skyline Corporation 

 

 

Florida is undeniably sunny. “The Sunshine State” was adopted as the State Nickname in 1970. It is used on FL_Sunshinemotor vehicle licenses, welcome signs and marketing campaigns. While Florida promotes itself as the Sunshine State we are not utilizing our most abundant and natural resource, solar power.

What is solar power? It is energy from the sun that is converted into thermal or electrical energy. Solar energy is the cleanest and most abundant renewable energy source available. The U.S., including Florida, provides some of the richest solar resources in the world. Only two other states, California and Texas, have more rooftop solar power potential than Florida, according to the U.S. Department of Energy. Based on Florida’s size, rebounding economy and growing population our state should be a leader in the generation and promotion of solar energy.

So why isn’t Florida a solar energy leader?

The reason is simple: Florida’s large utility monopolies and lawmakers have worked successfully to block and control who can generate solar energy and what it can be used for; thereby restricting its use by homeowners and businesses. Florida utility monopolies exist today due to a law that was created over 100 years ago which was trying to avoid a tangle of power lines strung up by competing companies.  This same law restricts solar companies from installing solar panels on roofs and selling back electricity. It is considered a third party sale and is illegal in Florida.

  • Florida is now only one of four states in the nation that prohibit citizens from buying electricity from companies that will put solar panels on a building.

Due to the influence and power of Florida’s utility monopolies, there is a large effort to discourage renewable energy in the state. The large utilities are afraid of losing their monopoly and the lucrative profits that the government guarantees them. Recently lawmakers, at the direction of the utility companies, gutted the State’s energy savings goals and entirely eliminated Florida’s solar-rebate program.

Floridians should have access to solar power and free market choices. We should be allowed to contract directly with solar providers to power our homes and businesses with solar energy. We are currently being denied the right to choose solar as a power source. The free market and competition benefits all of us. Solar energy makes financial sense. That is why business leaders in America’s brightest, most competitive companies are increasingly choosing to install solar energy systems at their facilities. The price of solar energy has fallen dramatically over the past few years while the price of fossil fuel generation continues to experience volatility. America’s businesses are turning to solar power because it’s good for their bottom line.

  • According to a report by the Solar Energy Industries Association, Walmart is the top corporate user in the United States with 105 MW installed at 254 locations.
  • The average price of an installed commercial PV (photovoltaic) project in 2Q2014 was 14% less than the cost in 2013 and was over 45% less than it cost to complete in 2012.

Electricity costs represent a significant operating expense, and solar provides the means to reduce costs and hedge against electricity price increases.

  • The Solar Means Business report noted that the top 25 companies for solar capacity had more than 569 MW of solar PV at 1,110 different facilities in a survey conducted last August. These results represent a 28% increase over the prior year and a 103% increase over 2012.

Clearly, solar power is a great untapped resource for the Sunshine State – one that can benefit residents as well as businesses. It is time to enable Floridians to have unfettered access to this inexpensive energy source – and you can help in the process:

The Florida resident-led solar group, Floridians for Solar Choice, is seeking to make solar more accessible in the state. They are seeking your signature on a ballot petition.

  • The petition seeks to expand solar choice by allowing customers the option to power their homes or businesses with solar power and chose who provides it to them.

Floridians for Solar Choice have reached 72,000 signatures on their petition which clears the way for it to be reviewed by Florida’s Supreme Court.

  • The Supreme Court will decide whether or not the petitions language legally qualifies it to be a ballot initiative for Floridians in 2016.

Getting its petition on the 2016 ballot is the main goal for Floridians for Solar Choice. They need over 600,000 more signatures to have this critical citizen initiative to be put on the ballot for next year.

Please visit their website to learn about the solar initiative to remove this legal barrier to making Florida the Sunshine State again, and, more importantly, to sign the petition, go to: www.FLsolarchoice.org.

Solar Roadways ‘Could Power America’

Posted on by abrahamwien18

May 27, 2014 by Leon Walker
View the original article here

An Idaho couple is using the Internet to fund their Solar Roadways project that would convert roads and highways into photovoltaic arrays, which they say could produce enough energy to power the entire US.

Scott and Julie Brusaw are using crowd-funding website Indiegogo in an attempt to raise $1 million to manufacture the product commercially, reports SingularityHub.

The product (artist’s impression pictured) previously received two rounds of funding from the Federal Highways Administration, buy that contract is set to expire in July.

Solar Roadways is a modular paving system of hexagonal solar panels that can withstand up to 250,000 pounds of pressure. These panels can be installed on roads, parking lots, driveways, sidewalks and bike paths, and the panels contain LEDs that road managers can light up to display lane lines and other road features that would traditionally be painted.
The surface of the panels, which are about the size of a car tire, is covered with hexagonal bumps that SingularityHub reports offer better traction than asphalt.

According to the crowd-funding website, panels pay for themselves primarily through the generation of electricity, which can power homes and businesses connected via driveways and parking lots. A nationwide system could produce more renewable energy than a country uses as a whole, the website says.

The roadways also have the ability to treat stormwater. Currently, over half of the pollution in US waterways comes from stormwater, according to Solar Roadways. The company has created stormwater treatment and storage areas in the pipelines used for housing cable.

Earlier this month, the Energy Department announced plans to use crowdsourcing in an attempt to spur innovation in the US solar marketplace.

10 US cities vow to slash emissions from buildings

Posted on by abrahamwien18

By ALICIA CHANG, AP Science Writer | January 29, 2014
View the original article here

LOS ANGELES (AP) — Mayors from 10 U.S. cities took aim at their skylines Wednesday, pledging to reduce greenhouse-gas emissions from their buildings.

Businesses and homes are a major source of carbon-dioxide pollution in cities, with most of it coming from the burning of fossil fuels for heating, cooling and lighting.

Many of the participating cities — Atlanta, Boston, Chicago, Denver, Houston, Kansas City, Mo., Los Angeles, Orlando, Fla., Philadelphia and Salt Lake City — already are working toward making their building stock more energy efficient.
Los Angeles last year became the first major city to require new and remodeled homes to sport “cool roofs” that reflect sunlight as part of an effort to save energy and reduce electricity bills.

Boston requires energy audits from building owners. The city, along with Chicago and Philadelphia, passed measures to track how much energy buildings are using as a first step toward boosting their efficiency.

Other places including LA, Atlanta, Denver, Chicago, Houston and Salt Lake City, participate in a voluntary federal program to cut energy waste from commercial and industrial buildings.

Under the new effort, cities will work with the Natural Resources Defense Council (NRDC) and the Institute for Market Transformation, a nonprofit that promotes green building, to continue their progress and further shrink their carbon footprints by targeting existing commercial and apartment buildings.

The groups projected the emission reductions would be equal to taking more than a million cars off the road, and they could save residents and businesses $1 billion annually. The project is funded by ex-New York City Mayor Michael Bloomberg’s foundation and other philanthropic groups, which invested $9 million for three years.

New York City managed to cut its emissions by persuading some landlords to switch from oil to natural gas, Bloomberg said.

Los Angeles Mayor Eric Garcetti said cities can be the matchmaker between building owners and banks that lend money for energy-efficient upgrades. He said greening buildings makes economic sense.

“We look forward to stealing your best ideas,” he told other mayors.

The cities were chosen for their geographic diversity, ambitions and ability to follow through, said project director Laurie Kerr of the NRDC.

The cities will craft their plans in the next several months. Backers acknowledged that some policies may require legislation. It’ll take several years to gauge whether cities met their emissions and savings goals.

Keith Crane, director of the environment, energy and economic development program at the Rand Corp. think tank, called the partnership a good first step. But he doesn’t consider it earth-shaking.

“It’ll have a modest effect on greenhouse gas emissions if everything goes right,” he said.

Right-Size Your Ventilation Needs

Posted on by abrahamwien18

Learn how demand control ventilation can reduce energy use

By Jennie Morton
View the original article here

Can ventilation requirements and energy conservation go hand in hand? They can if you implement demand control ventilation (DCV).

There’s no reason to waste energy conditioning air for people who aren’t in your building. Instead of supplying air at fixed rates, DCV automatically adjusts ventilation levels based on real-time occupancy measurements. This strategy allows you to meet code and reduce energy use without sacrificing indoor air quality.

EXHAUST YOUR OPTIONS
The problem with traditional ventilation is that it cannot distinguish between actual vs. projected occupancy. As outlined in ASHRAE 62.1-2013, Ventilation for Acceptable Indoor Air Quality, ventilation rates are calculated using two factors: square footage and peak occupancy.

Since square footage is a constant, any fluctuations on the occupancy side of the equation give rise to energy waste. With travel, sick days, vacation, and inclement weather, your building is rarely at capacity. In fact, human resources data shows an average of 75% of workers will be in attendance at any given time.

Without a way to calculate the actual headcount, your HVAC system operates as if maximum occupancy occurs on a continuous basis. If you can eliminate the excess air supply whenever fewer people are present, however, you have an opportunity to capture energy savings.

To have a responsive, intelligent HVAC system, you need to implement demand control ventilation. This strategy recognizes when a space has fewer people than scheduled and drops ventilation levels accordingly, explains Daniel Nall, senior vice president with Thornton Tomasetti, an engineering firm. Air supply is calculated using verified headcounts rather than occupancy projections. DCV is no different than using occupancy sensors to control lights – both ensure energy is conserved when there’s no activity in a space that justifies its use.

For example, offices need to supply 5 cubic feet per minute (cfm) per person in addition to a baseline of 0.06 cfm per square foot, Nall explains. Unoccupied, a 250-square-foot office needs 15 cfm to meet the ASHRAE standard. With one individual present, this increases to 20 cfm. Using DCV to sense when the room is empty, you can scale back the ventilation from 20 to 15 cfm, a 25% decrease in air supply. These savings are then multiplied across any room that has DCV capability.

If your occupancy variations are known in advance, DCV may be as simple as using a basic schedule in a building management system, says Jules C. Nohra, manager for energy efficiency at SourceOne, an energy consulting and management firm. Those with irregular or unforeseen occupancy fluctuations, however, will require sensors that can determine how many people are present. These include education, retail, conference areas, performance venues, lobbies, and offices with a mobile workforce or flex hours.

Carbon dioxide monitoring is by far the most common way to determine occupancy, says Thomas Lawrence, senior public service associate with the College of Engineering at the University of Georgia. The technology is well-established and straightforward to implement. CO2 isn’t treated as a contaminant that needs to have its levels controlled (a common misconception), but as a representation for the number of bodies in a space.

“Carbon dioxide measurements act as a surrogate for occupancy because humans generate an average volume per hour,” explains Nall. “By calculating the concentration differential between internal CO2 volumes and the outside air, you can estimate the number of people in your building. For example, if your CO2 concentration doubles, then occupancy has doubled.”

Occupancy sensors, such as the infrared ones you pair with lighting controls, can also be used. These are the most effective in individual work spaces and private offices, Lawrence observes. For a zone with multiple workers, however, they don’t offer fine enough measurements to calculate total attendance.

For example, think of an open floor plan that houses 30 people. The occupancy sensor will trip when the first person arrives, but it can’t scan the room an hour later to see if all 30 workers showed up that day. It also can’t detect if 15 of those employees move to another part of the building for a two-hour meeting, leaving the space over-ventilated during that period.

Entertainment venues may be able to use ticket sales to confirm a headcount. Other facilities can derive occupancy by counting cell phone signals present in the facility, Lawrence says. It’s also possible to have IT report the number of active computers, assuming that each device fired up represents a person in the space. If you use an access control system and it can interface with your BAS, each card swipe, keypad entry, or turnstile rotation can count toward occupancy.

INSTALL WITH AN AIR OF CONFIDENCE
Integrating demand control ventilation is heavily influenced by your existing HVAC system, such as whether your ventilation is combined with heating and cooling or is a standalone function.

“For example, adding DCV to a packaged rooftop unit may be as simple as including the CO2 sensor with a controller that has the DCV control logic built into it. Such a system likely serves only one or a few occupied zones, making it simpler to control CO2 levels,” explains Lawrence. “A larger building with central air handling, however, may serve many occupied zones. Determining the proper amount of outdoor air to bring in at the central air handling unit is also complicated by the variable occupancy patterns within the multiple zones.”

Say your VAV system supplies air to a large conference area and a group of private offices. To scale back the ventilation when the conference room is empty means that you risk the possibility of underventilating the offices at the same time. To avoid this scenario, you will need air flow sensors that measure the amount of air going to each space as well as the outside air that’s being drawn through the air handling unit, says Nall.

CO2 sensors are typically installed in the occupied space instead of ductwork because return air is an average of all conditioned spaces rather than an individual area, state ASHRAE members Mike Schell and Dan Inthout in their article Demand Control Ventilation Using CO2. Duct sensors can be used if all ventilated spaces share common occupancy patterns; otherwise, sensors should be wall-mounted.

“Avoid installing in areas near doors, air intakes or exhausts, or open windows,” advise Schell and Inthout. “Because people breathing on the sensor can affect the reading, find a location where it is unlikely that people will be standing in close proximity (2 feet) to the sensor. One sensor should be placed in each zone where occupancy is expected to vary. Sensors can be designed to operate with VAV-based zones or to control larger areas up to 5,000 square feet.”

Switching to DCV will typically require additional building management system points, new setpoints, and new control codes for dampers, Nohra notes. This may include a controller or DDC programming to communicate either directly with the economizer controller or a central control system, specifies the DOE in its 2012 report on demand control ventilation.
You should also make sure outdoor dampers are operable and not stuck in fixed positions, stresses Lawrence. It’s not unusual to find air intakes blocked in a misguided attempt to save energy. There may also be missing equipment, such as economizer controls with modulating air dampers that were specified but never installed.

Once the DCV sequencing has been established, the system requires minimal maintenance. CO2 sensors should be recalibrated periodically as their accuracy will drift over time. Consult your manufacturer guidelines, which may recommend recalibration every five years, annually, or every six months. Lawrence also recommends sensor testing prior to launch in case the product is deficient or was damaged during installation.

A BREEZY SOLUTION
Demand control ventilation isn’t a flashy energy efficiency project, but it consistently generates payback under five years or less. Paybacks can also be achieved more quickly if the system incorporates lighting and electrical outlets (vampire energy) controls. For upfront investments, owners can expect to pay less than $100 for occupancy sensors, Nall estimates. CO2 sensors can cost several hundred dollars per unit, adds Lawrence.

“The installation costs for a DCV project vary significantly depending on building size, existing infrastructure, and control requirements. An owner can expect to pay approximately $1,000 to $2,000 per point on average,” Nohra adds.
Nall was recently involved with a renovation project that incorporated DCV by using occupancy sensors. A series of perimeter offices and those adjacent to an atrium were paired with a dedicated outside air system and variable speed fan coils.

Each 160-square-foot office has a two-position damper. The default setting for an unoccupied office delivers 10 cfm of outside air. Anticipating occupant diversity when the office is in use, the secondary position is configured for three guests at 25 cfm.

“This ensures that we’re providing the minimum ventilation for the maximum expected occupancy,” Nall stresses.
Whenever the system senses the room is unoccupied, it can scale back ventilation to 40% of peak flow. The project cost less than $1,000 per office and since the occupancy sensor controls ambient lighting and power receptacles, the payback is under five years. The DCV capability also meets the LEED credit for increasing ventilation by 30%.

Lawrence also oversaw a DCV project at the University of Georgia. The retrofit converted a single classroom, but has seen great success since its installation. Payback was achieved in less than two years and there are plans to adapt more areas in the future.

“Regardless of the actual design standard, energy savings with a DCV retrofit should focus on a comparison to the existing ventilation patterns, even if they do not match current codes or standards,” emphasizes Lawrence. “If a building is not providing ventilation that meets existing standards, then the primary benefits of DCV are indoor air quality.”

Jennie Morton [email protected] is senior editor of BUILDINGS.

With Temperatures Dropping, Interest in Energy Savings at Multifamily Properties Should be Heating Up

Posted on by abrahamwien18

By Tal Eyal, FirstService Residential, 1/15/2014
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While winter made its official debut on December 21, the cold weather has been upon us for some time now and has gotten to extreme levels, including 20-year record lows across the country at the start of the year.
For boards, managers and other key decision-makers at multifamily housing properties, the dropping temperatures bring a rising interest in energy saving strategies, and a renewed focus on negotiating better utility rates. Facing a host of pressing management challenges throughout the year tends to put the issue of energy efficiency on the back burner. But each year, as the cost of heating common areas rises and fluctuates, the questions flare back up again: how can we save on costs and reduce our carbon footprint, and how can we help residents do the same? The fact is, by helping residents reduce their energy costs, properties are more likely to gain buy-in for those critical capital projects that come along.

With this in mind, some condo associations and executive groups have created energy committees to explore potential infrastructure improvements to common areas that create efficiency, and to determine how to negotiate better energy rates. Other HOAs—and rental property managers—have worked with their management companies to take concrete steps toward savings: conducting energy audits, implementing comprehensive energy conservation plans, and leveraging their collective purchasing power.

At FirstService Residential, for example, through our affiliate FS Energy, which focuses exclusively on energy management and advisory services, we have implemented a benchmarking and energy savings program for nearly 600 of our multifamily properties. The program, which began in New York City, has expanded to properties in Florida, and is launching in Chicago. In essence, the approach involves analyzing a building’s energy use and comparing it to similar structures; developing an energy maintenance plan to reduce consumption based on the findings of the initial analysis; and in the case of our northern properties, integrating an Energy Aggregation Purchasing Program to reduce natural gas and electricity costs.

The simple fact is that energy conservation is not just an important environmental goal, it should be a critical financial goal for every multifamily property. The correlation between better energy practices and real savings is irrefutable. Our program in NYC has realized more than $19 million in cost savings, while reducing the carbon footprint of our buildings by 68,630 metric tons, or 15.6 percent. We expect a similarly positive result in other regions of the country.

Ultimately, every multifamily property can benefit from some basic energy planning, along with some long-term infrastructure considerations. Some of the most important steps for properties to take include:
Conduct an energy audit: By assessing current energy usage patterns and costs, and by determining where conservation opportunities exist within a property, management can begin to develop a plan for savings. Every property that has not conducted a comprehensive energy audit should get one under way.

Pursue efficiency: Not only should boards and managers implement a procurement policy that prioritizes energy efficient products—including lighting, water heaters, and water saving devices—for common areas, they should develop a communications plan to encourage individual residents to take similar actions. Building management should consider offering regular energy savings tips in communications with owners and residents, along with opportunities to purchase energy efficient products at wholesale prices.

Train property management staff in energy conservation: Simple steps such as programming thermostats in common areas around usage patterns, and turning off lights in unoccupied rooms, can lead to savings. Staff should be trained to pursue strategies that reduce energy use.

Consider infrastructure improvements: Based on the outcome of their energy audit, properties may want to undertake more significant energy saving improvements, such better insulation, insulating window film, landscaping changes, and automated systems that monitor energy use.

While the winter weather puts energy use in the hot seat, the fact is that conservation and savings are year-round endeavors. Just consider the fact that in warmer climates, such as Florida and Southern California, cooling is the greatest expense. Even in New England, A/C use in the warmer months is a significant energy drain. With this in mind, decision-makers at multifamily properties should keep energy issues high on their list of priorities.

Tal Eyal is founder and president of FS Energy, the energy management subsidiary of FirstService Residential which advises residential property management clients of ways to reduce energy consumption, costs and emissions while improving property values and quality of life. Eyal oversees FS Energy’s operations, energy procurement business, as well as the data analysis and reporting of energy usage.