Factoid: ‘Nerds’ Find a Way to Breakthrough Cloudy Skies with Bacteria-Powered Solar

Published to LA Confidential, Summer 2018

Solar power is a renewable choice that many of our clients have embraced as part of a slew of solutions to lower their carbon footprint.  However, what happens when it’s cloudy outside, and the sun does not shine?  Bacteria-powered solar cells may be the solution!

Researchers (Sarvesh Kumar Srivastava, Przemyslaw Piwek, Sonal R. Ayakar, Arman Bonakdarpour, David P. Wilkinson, and Vikramaditya G. Yadav) from the University of British Columbia (UBC) have created bacteria-powered solar cells (i.e. biogenic cells) that work efficiently in dim and bright light. Meanwhile, prior attempts from other research through the extraction of light-sensitive dye from genetically modified bacteria proved to be costly and complex.

The UBC researchers used E. coli genetically engineered to produce an abundance of lycopene (a molecule that gives tomatoes their orange/red tint), which is a sufficient natural dye and is excellent at collecting sunlight. The team coated the E.coli in a mineral that can be used as a semiconductor and applied the bacteria/mineral blend to a glass surface to generate their biogenic solar cell. Professor Vikramaditya Yadav, the project leader, said they recorded the highest current density for a biogenic solar cell. The research has been published in the most recent edition of the journal Small.

Although this innovative technology shows promise, there are still glitches to be worked out. Unfortunately, it seems that bacteria does not survive the process. The key involves finding a process that does not kill the bacteria, so they can produce dye indefinitely. If the glitches in the technology can be fixed cloudy days may allow us to shine a bit brighter with solar power.

Source: Bacteria-Powered Solar Cells Make Electricity Even With Cloudy Skies


Benchmarking: A First Step to Finding Savings

Published to LA Confidential, Summer 2018

Benchmarking shows a building’s relative energy efficiency compared to its past usage, and to similar facilities in the same geographic area. Such comparisons may help a building manager grasp potential savings if energy system upgrades were applied. Thousands of buildings are now participating in voluntarily and mandatory benchmarking programs. Many have found the process useful, and some may find that it offers a few surprises.

The main goal of such scoring is to inform a facility’s management about the scale of potential savings if it deploys now-common efficiency options, such as LED lighting, variable speed motor drives, and building-wide energy management systems (EMS). Merely re-commissioning an existing EMS has reaped significant reductions in energy bills and greenhouse gas emissions. The United States Environmental Protection Agency (EPA) states that buildings with a benchmark score of 75 in its Portfolio Manager program may use 35% less energy and cost $0.54 less per square foot to operate than its peers.

To decide which option(s) may best boost a benchmark score requires an understanding of how a building uses energy, through an audit performed by experienced energy analysts (aka “energy nerds). When a low score merely elicits that small step, it will have done its job. However, many building managers have gone a step further by engaging in demand response, and developing on-site power systems such as cogeneration and solar panels.

As of early 2017, about two dozen large cities or states (map below) have implemented mandatory energy benchmarking programs for many commercial and institutional buildings, based on square footage and ownership (some apply only to public buildings). Most of those ordinances involve use of EPA’s Portfolio Manager (PM) program, which has become the U.S. standard for voluntary and mandatory benchmarking.


To compare among buildings, PM uses the U.S. Department of Energy’s Commercial Building Energy Consumption Survey (CBECS) database, covering about a million buildings. Every 3 years, it gathers energy data for 17 types of buildings, sorting them based on size, age, purpose, etc.

The end result is a set of tables PM uses to develop a percentile curve for each building type. If a particular type, such as a courthouse, uses less energy per square foot than the median for that type in its federal geographic district (e.g., the Northeast), it achieves a score above 50 (on a scale of 1 to 100). Note that a median is not the same as an average. It is based on quantities of entries, not an average of the values of those entries. If a facility manager (or owner, or board of trustees) sees a low score for its facility, it may be urged to apply upgrades to raise it. A building with a score of at least 75 may apply for ENERGY STAR certification and a decal to highlight its success.

As buildings cut their energy use and shift the curve, updating the CBECS database will result in lower PM scores. After August 26, 2018, a typical office building may see its score drop by 12 to 13 points relative to last year’s postings. All past scores will be automatically updated based on the new data, so facilities with a good score, (e.g., 61), may experience “PM shock” if it drops to an unacceptable 49.

Since 2009, New York City’s Local Law 84 (LL84) has driven the benchmarking of buildings with gross floor area over 50,000 square feet (10,000 square feet if NYC-operated). The Department of Buildings plans to include benchmarking of mid-size buildings (25,000-50,000 square feet). Facilities are advised to annually check the covered buildings list for their property. Properties on this list must submit data for energy use to the City annually to satisfy law requirements. If the property also has a “Yes” in the “Is this required to report automated water data from DEP?” column, automated data for water use from the Department of Environmental Protection (DEP) must be submitted. Occasionally, there may be a difference between your records and this list. If you believe a property should (or should not) be on the list, email benchmarking@finance.nyc.gov . A property’s status may change from yearly, so be sure to review the newest Covered Buildings List annually. A new list is available every February.

To offer additional incentive to improve efficiency, the City publicizes PM scores encouraging those with low scores to act. In 2020, The City will double down on the idea by labeling buildings’ entrances with grades (A-F) reflecting its PM scores.

Visit the ENERGY STAR Buildings & Plants page for free tips to improve scores. For professional guidance on making it actually happen, contact Luthin Associates. We have some of the best “nerds” in the business.

Will LEED’s New Focus on Energy Help Your Facility?

Published to LA Confidential, Summer 2018

The Leadership in Energy and Environmental Design (LEED) program was created and is maintained by the U.S. Green Building Council (USGBC), a private non-governmental organization. While a step toward improving general sustainability in buildings, the “energy” in the LEED name led many people to believe it would place energy efficiency high on its list of suggested activities. Fossil fuel consumption by buildings, either directly or via electricity use, is one of the largest contributors of the greenhouse gases that impact climate change, the foremost challenge to our future sustainability.

However, as noted in 2017 by the Institute for Market Transformation: “LEED certification does not guarantee that a building is energy efficient, as there are many factors that contribute to the accrual of points which correspond with certification — points related to energy performance are accrued alongside points related to occupancy comfort, landscaping, building materials, among others.”

To educate and set standards for sustainability in existing (as versus new) buildings, in 2007 USGBC created LEED Operation & Maintenance (O&M), now referred to as LEED for Existing Buildings. Among the characteristics mentioned above, a relative few relate to energy efficiency. In its original form, LEED for Existing Buildings awarded only 2 to 15 points out of nearly 100 for it, based on scores from the Portfolio Manager (PM) program (see “Benchmarking: A First Step to Finding Savings” for background on PM).

In LEED’s fourth iteration (V4.0), many changes in the point ranking system have increased energy efficiency’s prominence. Some energy-related prerequisites were dropped, while new credits (e.g., demand response) were added. As stated in its promos, “starting with a focus on reducing energy demand through guidance related to energy usage and efficiency, and then also rewarding renewables, LEED raises the bar on energy and offers new solutions for achieving goals.”

Most noteworthy is the incorporation of the PM benchmarking process into LEED’s new Arc performance platform, which tracks annual energy performance against that of comparable buildings. Arc subsumes PM by incorporating PM data entry into the annual LEED re-certification process. To manage it, a partner of USGBC (Green Building Certification Inc.), spun off a separate company (Arcskoru Inc.) in December 2016. It claims that “Arc is the first-of-its kind platform to track a building’s incremental improvements through a performance score.” Some cities began using Arc in 2017.

However, regardless of such improvements, how does a LEED score help a building manager or owner use less energy and/or switch to renewable energy? LEED’s manual does contain a variety of recommendations for cutting energy use and cost, but little beyond the free information available from EPA’s ENERGY STAR program. Perhaps the main improvement will come by directing the attention of facilities already in the LEED program toward raising their LEED scores via energy efficiency and renewable resources. As for those not presently seeking or holding LEED status, the V4.0 changes are unlikely to help.

The complexities of maintaining LEED certification, like many energy-related tasks, can be daunting for facility and building managers. Luthin Associates has years of experience with such programs and stands ready to assist your organization in achieving, upholding, and raising its LEED score.

Con Ed Rolls out Smart Meter Data to All Customers

Published to LA Confidential, Summer 2018

While monthly energy use data is essential for benchmarking, interval data (e.g., usage in 15-minute or hourly periods) provides a wealth of additional insights on how a facility uses energy. For many years, Con Ed’s largest customers have had access to such data via meters that send data to the utility via telephone landlines or more recently via cellular communications. Often sporadic due to metering and communication problems, that process will soon be consigned to the technology scrap heap by new smart meters under the utility’s Automated Metering Infrastructure (AMI) program.

Con Ed is replacing all electric meters by 2022 with units providing 15-minute consumption data for residential customers and 5 minute data for commercial billed customers. New smart gas modules will also be installed in the CECONY gas territory providing hourly data. That program (covering 4.8 million meters) is already underway. Find out when your borough (or county) will be involved at the Con Edison Smart Meter Installation page. All meters are being replaced, regardless of load, based on geographic location. As a result, many residential customers will have smart meters long before the commercial and industrial users that could make more immediate use of the data.

No action, aside from giving access to the existing meters, is required by customers. Con Ed is sending notification postcards to customers approximately 3 months in advance, followed by a letter about 45 days before its blue Smart Meter truck arrives. The actual work is painless, though there may be a brief pause in electric power during the meter replacement process. Online access to AMI data – at Con Ed’s MyAccount dashboard – should be available approximately two weeks after a new meter is installed. MyAccount provides tools for commercial customers to view their data with a weather overlay, or compare usage by hour, day, month or year. Customers can also download their interval data from MyAccount using the Green Button Download My Data tool.

Customers may then use their interval data to focus on issues that impact bills, (e.g., exactly when, and how often, a peak demand occurs), providing clues on ways to reduce it. Many customers chart interval data into daily load profiles to reveal night and weekend usage of equipment that should instead be shut off. Below see before-and-after 24-hour load profiles for one site. The cross-hatched area shows one day’s saved kilowatt-hours after the building’s equipment and energy management system were more tightly controlled.


Demand response (which requires interval data) may also become more viable as customers use their interval data to parse out major demand components with any eye to installing variable speed drives (or two-speed motors), dimming systems for lighting, or other measures to cut load when needed. Integrating solar and cogeneration into a building also becomes easier (and less financially risky) when a customer has a firm grasp on when on-site power will yield the best payback.

Con Ed will use data from its AMI system to improve its grid by giving it a deeper understanding of sub-hourly usage and voltages within its distribution lines, allowing for better voltage control, which will reduce energy consumption, and better outage response.

Securing the greatest value and understanding of interval data is enhanced by an expert’s eye, such as those offered by Luthin Associates. We have a long history of working with such data to help our customers save money and energy, while shrinking their carbon footprints.

Factoid: Exploring the Possibility of Solar Energy from the Moon

Published to LA Confidential, Winter 2018

We have often wondered, ‘Does life exist on other planets?’ Although we may not have infinite answers to extraterrestrial life on other planets, one concept that does exist out there is potential energy. Specifically, the possibility for lunar-based solar power (LSP).

According to a 2017 Forbes article, the concept of LSP involves developing solar power collecting stations on the Moon’s surface, which would convert sunlight into electricity and be wirelessly transmitted to Earth. Supporting this concept of a more sustainable source of clean electricity by using solar panels to collect sunlight on the Moon is retired University of Houston physicist, David Criswell.

By Criswell’s own models of his proposed 20 terawatt LSP system, he provides an eventual projected wholesale price of 0.001 cents per kilowatt hours (kWh) of electricity. At present, an average American household pays in the range of 12 cents per kWh. By comparison, the future not only appears to be built on the complete use of clean energy, but the possibility of LSP may lead to significant savings. Although it is a fantastic idea to ‘Klingon’ to, the idea of LSP may still be lightyears away.

Source: Physicist Wants To Beam Solar Energy Back From Moon’s Surface

Working out the Tribbles of On-Site Power Storage

Published to LA Confidential, Winter 2018

On-site battery power storage is a hot new energy option, but it does not come trouble-free. As Captain Kirk learned in Star Treks “Troubles with Tribbles” episode, some problems are easier to solve than others.

At this time, most utility batteries are being installed to manage frequency regulation, provide synchronized reserves, and other ancillary services of interest solely to grid operators. How much a retail power customer may save by installing a battery system, however, depends on a customer’s utility tariff rate, and how the power storage system is operated.

There is no question that the state of the art in battery storage systems is advancing rapidly, while at the same time, expanding production capability at locations such as Tesla’s “Gigafactory” is causing prices to fall significantly (in dollars per kWh of storage capability). Following a trajectory much like solar photovoltaic (PV) systems, battery storage is becoming cost effective in more and more applications.

While battery pricing has been rapidly dropping, care is needed to consider the balance-of-system expenses that can significantly increase total installed cost. But even if costs fall enough to yield an attractive payback, is power storage an out of this world option? Not necessarily. Let us look at a few of the other “tribbles” that need to be addressed, regardless of pricing.

Fire codes – While a few applications of batteries (e.g., “hoverboards”) have given some people pause about installing them in their buildings, recent New York City Fire Department regulations on stationary lithium-ion batteries have favorably addressed fire prevention and suppression concerns. In a 97-page report issued earlier this year, NYSERDA and the City found that “The installation of battery systems into buildings introduces risks, though these are manageable within existing building codes and firefighting methods when appropriate conditions are met.”

Regarding a potential fire, the study found that the batteries it tested emitted toxic gasses that may be “mitigated with ventilation rates common to many occupied spaces” finding that “toxicity is similar to a plastics fire” already a factor in most office environments with their computers, copiers, printers and furniture. Among the other key findings in the report are that water, by far the most common fire suppression agent, is the most effective extinguisher for a battery fire, and that thermal runaway (i.e., fire spread among battery cells) may be addressed by cell module design.

Space and weight considerations – Any battery big enough to actually manage a building’s daily peak load will be large and heavy. While basement floors may be capable of holding stacked battery cells, locating on an upper floor or roof may require structural enhancements.

Leasing issues – To get around the high first cost, a few firms lease their batteries to customers. They secure the large dollar utility and/or governmental incentives up front, and the leases offer them a guaranteed revenue stream for 7 seven (or more) years. Customers need to understand that a lease does not assure that power storage will indeed cut their electric bills. Smart battery software is needed to optimize charging and output, with a performance guarantee that delivers a stated minimum savings, or a payment if it is not achieved.

Software – Key to securing serious dollar savings are the algorithms (i.e., computer formulae) that determine when, and how much, power should be stored or discharged. At this time, there is no easy and standardized way to compare them. A good program needs algorithms that, in real time, take into account:

  • Supply price/tariff structures, and/or a third party’s contract terms.
  • Day Ahead and hour-ahead wholesale supply pricing.
  • Seasonality and timing of the existing delivery tariff.
  • Wholesale ancillary service opportunities and requirements (e.g., response time).
  • Facility’s recent and projected daily load and reactive power profiles.
  • Projected output profile of on-site generation (e.g., solar PV system).
  • Projected weather conditions.
  • Battery condition/degradation.

Navigating such issues requires expertise in tariffs, power procurement, and energy contracting. Luthin Associates has all three, and would be happy to offer its guidance to customers ready to explore the options of power storage.

For a more extensive explanation, please click on the link for the related article: The elusive art of predicting energy storage savings in the real world


Beaming up Best Paybacks at a 271-Year Old Institution

Published to LA Confidential, Winter 2018

Bill Broadhurst has been Princeton University’s energy manager since 2009. During those 8 years, he has handled challenges that range from raising efficiency in buildings built before the American Revolution, to designing state-of-the art systems for 21st century facilities.

Princeton’s 10 million square foot campus in New Jersey has an advanced central plant, equipped with dual-fueled boilers and cogeneration, variable-speed pumps and motors, thermal energy storage, and free cooling through its cooling towers. Cogeneration, Thermal Storage and Steam-driven turbine chillers minimize peak demand charges for cooling, and a centralized geothermal system is on the drawing boards. Power delivery to the campus from the local utility is on a high-tension real-time pricing tariff, with supply purchased from a competitive third-party supplier.

With HVAC and lighting systems installed literally across centuries, Broadhurst has found ways to enhance energy efficiency wherever possible, while meeting the University’s climate change goals. Those efforts have resulted in 70-80% of the facility’s lighting being converted to LED, and DDC controls installed in most of its 150 buildings. About half of them are optimized via control system optimization software run by his operators monthly. While all new buildings have hydronic heating systems, many of the older structures still have steam radiation. Broadhurst has replaced over 5,000 steam traps in them, plus a variety of other controls.

In those older buildings, he has had to deal with asbestos, rusted pipes, and the need to preserve their historical and architectural integrity, including many antiquated light fixtures. Even upgrading tubular fluorescent fixtures has been an occasional challenge. “To meet budgetary constraints, we switched out those lamps with Type A tubular LEDs (TLED)”, said Broadhurst. “Those are the ones that use a fixture’s existing ballasts. While Type B and C units [which use internal or external LED drivers] might have been more energy efficient, that would have required electricians to service since the safety labels on the fixtures might not be read or seen by janitorial staff.” As part of that upgrade, most fixtures are now controlled by occupancy sensors.

Pre-energy crisis HVAC equipment has also offered challenges. Old hot/cold deck and dual duct distribution systems, as well as unit heaters and terminal A/C units, must be renovated instead of being scrapped due to the high cost of replacing them with modern units. But Broadhurst continues to find ways to make them more energy efficient. Pneumatic controls have been replaced with digital controls. Many fan coil units are also controlled by occupancy sensors. Other energy-related systems have not escaped his eye: even domestic hot water piping has been insulated.

Princeton is now getting ready to embark on its next 10-year capital plan, and Broadhurst has a wish list of energy carbon-cutting options. With his skill and perseverance, he may indeed “go where no energy manager has gone before.”