Solect Services Advisories

 

Internet Connectivity

Our goal is to ensure that your solar array is operating at peak capacity 24/7. However, the data we need to monitor your array is dependent on your system being able to communicate with our service hub. Power outages from severe storms can impact internet connections, and inhibit our ability to effectively monitor your array’s production.

Considering that internet performance is most likely to be impacted under the same conditions that could potentially affect your array’s performance, it’s imperative to ensure your internet is functioning properly after a major weather event. If a problem does arise, a fully functional internet connection empowers your maintenance provider to be able to respond quickly and ensure your array is producing as efficiently as possible.

 

 

Inverter Care

Inverters are designed for outdoor use, however additional measures can be taken to ensure both the longevity and performance of your inverter.  Here are tips from two of the most common inverters we support, string inverters and central inverters.

String Inverters:  Inverter manufacturers have recently recommended shade covers be sold with all of their string inverters to avoid overheating. Excessive sun on the inverters have been known to reduce the overall performance of the inverters and in some cases damage the displays on the inverter making it difficult to read and support.   

 

 

Central Inverters:For central inverters that are installed outside next to a building, we recommend our customers protect these systems from direct sun as well.  The inverter cover featured here not only protects the inverter from the sun, but also from falling ice. It also has built-in bollards that protect the inverters from ground oriented threats such as car traffic. 

 

 

 

Inverters are one of the most important components of your Solar system. As the industry evolves, best practices are emerging that help extend the life and performance of this crucial hardware. Solect is here to be your solar asset partner helping you achieve the highest possible return on your Investment by keeping you up-to-date on the latest best practices in solar maintenance.

EEAC Releases Final Proposal for Massachusetts Energy Efficiency Program

The EEAC recently released the latest updated proposal for the state’s 3-year energy efficiency plan, set to run from 2019-2021. Prior to the release of the EEAC’s final proposal, Solect Energy’s VP of Energy Solutions, John Mosher, wrote an article featured in the BBJ, outlining what he thought the most impactful initiatives would be in the interest of preserving Massachusetts’ status as a nationwide leader in energy efficiency measures.

While the rulings for the projected $2.65 billion dollar program don’t quite align with what we were hoping to see, they do include some important opportunities for the advancement of the Bay State’s energy profile. The most glaring difference between Mosher’s proposed changes and the EEAC’s final ruling, is the absence of a rebate program for storage deployment of any kind.

Instead, the EEAC presented a “technology agnostic” incentive program that will reward organizations for achieving peak demand reductions, regardless of how they are accomplished. The key here is the timing and risk associated for any organization looking to pursue a demand-reduction project, such as battery storage as a way of addressing their demand charges. For instance, while battery storage effectiveness is well documented, the EEAC has opted to put the impetus on the consumer to install a solution and achieve the demand reduction before rewarding them for pursuing a battery installation. This concept works in the sense that they will be rewarding for results, rather than action. However, it leaves business owners to shoulder the costs of the installation up front, while waiting to receive any assistance until after the the project has been proven successful. This does little to remove the primary barrier to entry, substantial upfront costs, in an emerging technology like energy storage. Perhaps once the parameters for “proving demand reduction” are outlined more clearly we will be able to forecast the programs efficacy more accurately, but for now very much is still left uncertain.

The structure of the program essentially revolves around customers responding to an “event call targeting condition” issued by “curtailment service providers” (CSPs). The benefit in this approach is that it allows a customer who installs battery storage to also implement other actions, such as powering down operating equipment, to further reduce their demand when the call is made. Overall, the best aspect of the EEAC’s updated plan, is that it encourages business owners to become more involved  with their energy profile, and invites them to be part of the solution for their communities’ energy demands. However, the ad hoc approach, undefined regulations, and frequency of “event calls” currently leave very much up for interpretation, and we are eager to see just how the program evolves leading up to its implementation.

Staying on Top of your Energy Consumption with Demand Monitoring

Gain insight into your energy use and manage your expenses with Demand Monitoring solutions

 

If you’re like me, I’m sure you have had those moments when your energy bill arrives and you find yourself saying “can that be right?” With all of the stifling heat this summer and HVAC systems working overtime to keep up, many building owners or their tenants are probably thinking the same thing. Well, it’s not a crazy question to ask.  Although usage accuracy is important for utilities, meters and other systems can malfunction and occasionally may result in over-billing.

So if you find yourself questioning a bill, there is now a way you can check to see if it really is accurate. Demand monitoring is an approach that has been gaining traction with many building owners. A demand monitoring system allows you to measure your building’s energy consumption. It can be customized based on your needs and building parameters, for example,  allowing building owners to measure the energy consumption for each tenant.

Another advantage applies to solar energy systems. A demand monitoring system can show you exactly what the solar energy system is producing and how much power you, or your tenants are using. In Massachusetts, under the SREC program, solar energy systems needed to be paired with the load of the building occupant; with a demand monitoring system it’s now easy to see what is happening.

Demand monitoring systems can also tell you how you are using your energy. They will be able to identify your peak energy usage. This is important because utilities assess “demand charges” based on these peak periods. Once you know the peak, you can take steps to better manage your load and flatten out your usage. This could also tell you if you might be a candidate for an energy storage system which can be charged during times of low usage and deployed during peak times.

The above chart shows a prime example of a solar array that produces most or all of the building’s mid-day consumption, but may not be reducing monthly peak demand charges. This system would be a perfect fit for a solar + storage solution that would store the extra energy produced during the day for use during the unaddressed peak periods.

Lastly, installing a demand monitoring system is relatively simple. It requires a data logger and installation of a few CT (Current Transformer) meters that measure the supply of current. Software systems can track the data and provide other options like dashboards and invoicing services. A reputable energy services company will typically offer demand monitoring services and the price is usually quite reasonable. So if you are still wondering about those energy bills, it might be worth taking a closer look at demand monitoring.

 

Athletic Facility Solar Success Stories

Athletic facilities have notoriously high operating costs, and don’t have a lot of flexibility to adjust their practices to save money going forward. From complex HVAC systems, to industrial scale lighting, these expansive facilities can be challenging to maintain throughout the volatile New England seasons. Furthermore, many of these facilities are non-profits whose operating margins are slim to begin with, making coping with the fluctuating energy premiums challenging at best. Luckily, many of these facilities also have large, open roofs, making them an ideal fit for a solar energy installation. Below we have highlighted a number of the successful partnerships we’ve formed with arenas, rinks, gyms, and more across New England.

 

 

Stonehill Athletic Building

Location: Easton, MA

System Size: 460 kW

Panels Installed: 1,518

Installation Date: January, 2015

Stonehill College has made a continued effort to bolster their sustainable practices over the last several years, with the first among them coming back in 2013, when they added a large solar canopy to help power the school as a whole. After seeing the impact it had on their energy expenses they looked to address the energy costs for one of the biggest draws on campus, their field house. 

 

Long Fellow Clubs

Location: Wayland, MA

System Size: 148 kW

Panels Installed: 564

Installation Date: December, 2014

Owners Laury Hammel and Myke Farricker wanted their business to be “as sustainable as possible,” while also being financially conscious. As a result they decided to take the PPA route to finance their installation, which allowed them to benefit from solar energy without having to make the upfront capital investment. The 148 kW system installed on the roof of the fitness club generates over 180,000 kWh of solar energy annually, covering at least 21% of the club’s electricity needs.

 

Pingree School

Location: South Hamilton, MA

System Size: 227 kW

Panels Installed: 770

Installation Date: March, 2013

The Pingree school has been an active member in its community since being founded in 1960, and is dedicated to demonstrating responsible and sustainable practices. The Johnson Ice Rink on their campus plays an important part in their athletic program and to the local community, however, the cost associated with running the facility is quite high. In fact, during the summer of 2011, a decision was made to shut down the rink during the summer partially due to the high cost of electricity. Once they realized that solar could solve this issue, they turned to Solect Energy to pursue a PPA installation. The 227 kW array on the roof of the ice rink has resulted in a 50% reduction in their energy costs, allowing Pingree to maintain year round operations of the rink.

 

Beverly Athletics

Location: Beverly, MA

System Size: 128 kW

Panels Installed: 320

Installation Date: December, 2017

Like most active business owners, Ed Soul, the owner of Beverly Athletic Club, was looking to pursue any avenue to bolster his company’s operations. Having seen the benefits of solar energy in his town, he decided to partnered with our team here at Solect Energy to install a 128 kilowatt (kW) solar energy system on the athletic center’s roof.  The solar array consists of 320 photovoltaic (PV) panels and is expected to produce 155,041 kilowatt hours (kwH) of energy annually. The power generated will cover 33 percent of the BAC’s energy needs, and is equivalent to the annual charging of 7,752 electric vehicles or 31,008,200 smart phones. It is projected that BAC will save approximately $233,000 over the course of 10 years.

 

 

Fore Kicks

Location: Norfolk, Marlborough, Taunton, MA

System Size: 888 kW

Panels Installed: 3600

Installation Date: May, 2012

With several expansive facilities and demanding lighting, heating, and HVAC systems Forekicks was faced with a myriad of challenging energy bills and wanted to avoid raising costs for their membership programs for fear of pricing out families in their communities. Forekicks began a commitment to energy efficient green operation across their family of facilities. Solar was the logical next step in their evolution, with their newest facility being built/oriented to maximize their north/south exposure. By installing three arrays across their facilities in Marlborough, Norfolk and Taunton, Fore Kicks add over 880 kW of solar to the roofs of their buildings, to join the energy-efficient lighting systems (LED is being explored) and HVAC systems, and on-site recycling programs. Fore Kicks was able to put their energy expenses in check, and keep their programs affordable.

 

Metrowest YMCA

Location: Framingham, MA

System Size: 144 kW

Panels Installed: 374

Installation Date: June, 2017

For more than 55 years, the MetroWest YMCA, has responded to community needs in the MetroWest area and made a significant impact throughout Framingham and the surrounding towns. MetroWest YMCA anticipates the array will provide up to 13 percent of its facility’s annual electricity, for a projected yearly savings of more than $10,000. The MetroWest YMCA had also been doing its part to become more environmentally sustainable by encouraging recycling, conserving energy with responsible use policies, and LED lighting initiatives. The addition of solar is a significant step forward in the organization’s sustainability commitment.

 

 

Clark Memorial YMCA

Location: Winchendon, MA

System Size: 275 kW

Panels Installed: 888

Installation Date: October, 2016

Like most nonprofits, The Clark Memorial YMCA is always looking for opportunities to better serve their members, and as with any large athletic facility their spending on energy was significant. Solar energy presented an opportunity for them to reduce their energy expenditures, and thanks to their relationship with PowerOptions, they had an easy avenue to install a solar array. After pursuing the opportunity the Clark YMCA installed two arrays totaling 275 kilowatt (kW) on the roof of its field house and main building in Winchendon, MA. The solar arrays are expected to cover over 80% of the facility’s annual electricity use, and save the organization over $18,000 a year.

 

Charles Moore Arena

Location: Orleans, MA

System Size: 345 kW

Panels Installed: 960

Installation Date: August, 2017

Charles Moore Arena (CMA), a nonprofit ice rink in Orleans, MA, faced the same challenges as many of its peers; high operating costs, with tight margins, and unpredictable conditions. Considering the high energy prices in Massachusetts, keeping an ice rink running at optimal levels during the sweltering summer months is no easy task. By collaborating with Solect Energy, CMA was able to install a 345 kilowatt (kW) rooftop solar system at the arena using a PPA financing model, which allowed them to avoid the upfront investment, while still reaping the benefits of solar. The installation will help stabilize and reduce their biggest operating outlay, as the array will cover 50% of their energy demands.

 

Considering Solar and Need a New Roof?

One of the most common barriers for commercial property owners who want to install a solar energy system is the age and condition of their roof. Minor repairs such as seams and flashing can easily be addressed, but many owners need more significant upgrades and some require complete replacements. But what if adding a solar energy system to your roof could help pay for roof upgrades, and in some cases an entire new roof?

Starting this fall, Massachusetts is introducing a new solar incentive program called Solar Massachusetts Renewable Target program (SMART) where building owners will now have the option to install “stand alone” projects where the energy is sold directly to their utility at a predetermined price for 20 years.  

This means property owners don’t have to find tenants or other off takers for the energy produced.  Also it eliminates the need for power purchase agreements and billing to get compensated for the energy produced. Under the current SREC program the incentive is paid quarterly and the value is not fixed but subject to the market pricing that changes quarterly. Under the new SMART program the incentive is included in the monthly tariff payment to the array owner by the utility and is fixed for 20 years! Also the “customer” for the power is an investment grade credit entity, your utility. The combination of an investment grade credit and fixed monthly payments has allowed solar developers to structure deals for property owners that include the costs of roof upgrades and even new roofs with the solar project.

Let’s take a closer look at how this works. Under the new incentive program, a standalone project essentially means that a solar energy provider is leasing your rooftop. The solar company will own the system and be responsible for operating and maintaining it, you are just leasing them your rooftop. Because the project’s “offtaker” is now the utility, this allows solar providers to secure better terms for the financing of their projects. In turn, this allows solar developers to give more options to building owners including ongoing lease payments, or in some cases, an entire upfront payment that could provide enough cash for a new roof.

The new SMART program will reward property owners for investing in solar with a fixed monthly incentive that is truly “bankable.” So, if you have been considering exploring the benefits of solar energy, or if your need a new roof on your building, the timing has never been better! Contact a qualified solar provider and they can work with you to better understand your options under the new SMART program.

 

Commercial, Industrial & Institutional Facilities are the Next Frontier for Energy Storage

 

Game changing energy storage technologies will fundamentally alter the functionality of the electric supply system: What this means for energy consumers, and why commercial facilities should be considering it today.

As we consider the future of the built environment, one of the most dramatic changes will be the way we generate and consume electricity. The challenge to decarbonize our energy supply has created a myriad of opportunities for new ways to generate, manage and consume power. Over the last decade, clean energy technologies like solar and wind have been complimented by super-efficient technologies like LED lighting and new heating and cooling technologies, resulting in lower costs for consumers and fewer emissions. Energy storage is the critical third leg of this stool, the lynchpin that enables more rapid penetration of new efficiency technologies and clean energy generation.

Why energy storage is important

Because electric power cannot be stored, it requires the overbuilding of our energy systems with a vast amount of expensive, and often dirty, capacity waiting on the sidelines ready to be called upon during periods of peak demand. For example, a recent study by the Department of Energy Resources in Massachusetts calculates that the top 1% of peak energy demand for the state represents 10% of the overall supply costs and that the top 10% of peak demand represents 40% of total energy supply costs.[1] Energy storage gives grid operators much more control in managing their load. Batteries can be charged in periods of low demand and deployed when energy  is needed. It also allows energy resources to be located closer to where the energy is required, relieving congested nodes on the grid and reducing the need to upgrade distribution systems.

In recent years, as the world has begun to address the carbon intensity of electric power supplies, we have seen a significant deployment of clean energy generating sources. Much of this new capacity has come from solar and wind energy which are “intermittent” resources, meaning that they produce power dependent on the wind blowing and the sun shining.  At higher levels of penetration, intermittency can create additional burdens for managing the grid; not producing enough power when it’s needed or producing too much power when the grid can not accommodate it. A well known pattern of solar energy production is called the “duck curve” (see image below) where solar energy systems deliver maximum output during the middle of the day, but then trail off as the grid hits its peak in the evening. Energy storage can help to balance these intermittent resources and smooth out load problems like the duck curve.

The “Duck Curve:” Image from California Independent System Operator

Another important benefit of energy storage is resiliency, as a battery system can allow a facility to continue operations during a power outage. This is especially important for critical infrastructure like hospitals and public safety facilities. Traditionally these facilities have often relied on diesel generators for backup power, but with the penetration of on-site solar, declining battery costs and the ability to avoid demand charges, storage is becoming an attractive and cost effective option to enhance resiliency.

With the expense of building a grid that needs to ramp-up on a moments notice to meet demand, and a growing amount of intermittent generation sources from solar and wind, the ability to store energy becomes much more urgent. Historically, batteries have been too expensive to displace peaking assets on the grid, but with the plummeting costs of batteries this is rapidly changing, and may happen sooner than many think.

Early Deployment at Utility Scale

In European countries that were early adopters of storage friendly policies, energy storage has seen robust market penetration. According to Energy Storage News, 300 Megawatt (MW)  hours of energy storage was installed in the EU in 2015 which grew to 700 MW hours installed in 2017. 60% of the total installed capacity is utility scale. These are larger projects that benefit from scale efficiencies and are often referred to as “front of the meter.” This means it is a stand alone project that feeds power directly into the grid. Commercial and Industrial (C&I) projects are often called “behind the meter” as they sit behind the meter at a facility and provide on-site energy with benefits going directly to the energy consumer.

The C&I market is expected to see explosive growth over the next five years

A recent study by Delta Energy and Environment predicted that by 2021 up to 210 MWs of energy storage would be installed annually in Germany and the UK for C&I markets; this would be ten times the 22 MWs installed in 2016.[2] Like Europe, the U.S. has seen initial market penetration at the utility scale. However, behind the meter systems are expected to see tremendous growth in the next few years. A report by Green Tech Media and the Energy Storage Association forecasts the U.S. C&I market to grow 15 times its current size in 5 years (by 2023) reaching 3.3 Gigawatts (GW) of new annual capacity. By 2019, it is expected that behind the meter projects (residential and C&I) will comprise 50% of the new capacity.[3]

Behind the boom: a closer look at the economics of commercial and industrial energy consumers

To understand why C&I facilities are expected to see such rapid rates of adoption we need to take a closer look at how C&I customers are charged for their energy. Typically utilities charge commercial customers in two different ways. Most well known are volumetric charges, i.e. how much energy is consumed over a period of time. This is calculated in terms of kilowatt hours (kWh).  However, because of the expense of managing peak demand, many utilities will also send economic signals that encourage consumers to “flatten” their load; i.e. avoiding dramatic energy surges that will trigger the need to call upon more expensive generating assets.

The most common way that utilities send these signals is through demand charges. Although these charges can vary in the way they are calculated, typically a utility will look at a consumer’s peak load each month for a short duration of time, usually a fifteen minute window. The demand charge is calculated by taking the peak usage for each month and multiplying it by a certain rate. Unlike energy consumption charges, demand charges look only at a snapshot in time, and thus are based on kilowatts (kW) as opposed to the volumetric charges which are based on kilowatt hours (kWh).

For example, a small manufacturing company may have a big order due at the end of the month and utilize all of its machinery in a short period of time, causing a spike in its energy consumption. Let’s say their typical load is 750 KW but during the end of month surge it ramps up to 1200 KW. The rate for demand charges can vary from zero to as high as $50+/KW. Let’s assume $40/KW. This would translate to a monthly charge of $48,000, just for that one spike in energy consumption. Typically demand charges are anywhere from 30%-70% of a customer’s bill.

Price signals justify commercial scale energy storage projects today

High demand charges are sending price signals that are accelerating the energy storage market. In looking to mitigate these charges, facility and energy managers are looking for ways to even-out their load profiles. At the same time, commercial energy storage systems have rapidly declined in price, making storage an attractive option today. In fact, according to a study by the Clean Energy Group and the National Renewable Energy Laboratory (NREL), installing an energy storage system makes economic sense for customers who are paying more than $15/kW in demand charges. Based on this threshold, NREL determined that energy storage systems would make economic sense (2-5 year payback) for 5 million commercial customers in the US.[4] As policy makers establish incentive programs for energy storage, the numbers will become even more compelling.

In another study, NREL looked at two specific case studies for commercial facilities to determine the potential value of an energy storage system. The first project was in Los Angeles, CA and looked at a storage system paired with photovoltaic (PV) solar energy, and a second project in Knoxville TN that only had a battery system. Based on the potential performance of a lithium ion battery system, both projects had a positive Net Present Value (NPV); $31,874 for the Los Angeles project and $60,731 for the project in Knoxville.[5]

Incentives for Energy Storage:

Like Europe and other global markets, the rate of penetration for energy storage is dependent not only on the underlying market conditions but also government policies to jump start the market. In Europe, first Italy, then Germany and then the UK each created rapid growth as they rolled out storage friendly policies.  In the U.S., early stage markets are driven by state policies with the leader being California where a rebate program called the Self Generation Incentive Program (SGIP) drove 45 MW of new installed storage capacity for the C&I market in 2017. More recently, New York, New Jersey and Massachusetts have all launched new storage incentive programs. Of course federal policies are also important and customers who co-locate storage with solar, will be able to take advantage of the 30% Investment Tax credit and accelerated depreciation.

Types of Energy Storage:

Energy storage can come in multiple forms. Systems can range from pumped hydro to compressed air systems. For commercial facilities, we have already seen the use of thermal energy storage where buildings are heated or cooled during off-peak hours when electric prices are cheaper. We have also seen the deployment of ice systems that exploit the same arbitrage opportunity. Flywheels have been deployed to help with frequency modulation on the grid and flow batteries have the potential for longer-term storage requirements. For electrical power and the demands of the C&I market, lithium-ion batteries are currently the technology of choice. These systems are produced by reliable OEMs, require little maintenance and are easily installed at a commercial facility. Their “energy profiles” match well with storing energy from the grid or a solar energy system and then deploying that energy over shorter period of time to mitigate the demand charge by “peak shaving”.

 

An example of an installed DSS®Distributed Storage System ©2018 NEC Energy Solutions, Inc. – Used with Permission

 

Bringing intelligence to energy storage

As mentioned above, the preferred technology for C&I applications is a lithium ion battery. Although we are still seeing innovations in manufacturing that are driving down costs, the performance characteristics and longevity of lithium ion are well understood and predictable. However, a battery needs an operating system to tell it what do. This system needs to be sophisticated enough to understand when the facility load is at its peak and when to deploy its energy. Most commercial battery systems come with their own integration software or can be combined with other energy management software.

Over time, these systems will become increasingly sophisticated to factor in a variety of additional variables such as market pricing signals, time of use rates or even predictive models using weather, load and other data. This is called demand monitoring and many C&I customers are installing these software systems, even without storage, because it gives them in-depth insight into their energy load and the ability to control it. For example, they could sub-meter tenants or identify specific pieces of equipment that they wish to monitor in order to operate it more efficiently.

The Benefits of Pairing Solar and Storage

When combined with a solar energy system, energy storage essentially allows a facility to be self sufficient in that it can generate its own power, store it and use it as needed. However, although it is technically possible, the economics at this point do not favor disconnecting from the grid. The sizing requirements for a storage system large enough to be completely independent of the grid does not yet make economic sense in most market conditions. Instead, energy storage systems will be designed to lower costs through demand mitigation (reducing demand charges by reducing load spikes), arbitrage (for facilities with time of use rates) and back-up power that can keep facilities fully operating for a limited amount of time or a subset of critical systems for a longer period of time. Lastly, as policy makers continue to leverage the benefits of distributed generation and storage there are likely to be more opportunities for facilities to monetize their systems. This will give facility managers even more flexibility with their energy choices down the road.

Exploring the advantages of energy storage

Across the globe, policy makers are recognizing the benefits of energy storage and this is reflected in aggressive market forecasts. With large, complicated energy loads commercial, institutional and industrial facilities are ripe for storage deployment. In turn, the benefits to these entities go beyond cost savings giving them more control and optionality with their energy strategies, increasing their resiliency and helping them to achieve their sustainability goals.

However, for facility managers who are interested in pursuing these benefits the initial steps can be quite daunting. The best choice will be dependent on specific incentives, tariff structures and load profiles. If you think storage, or a combined solar and storage system might be a good fit for your facility, a reputable energy company should provide a basic assessment free of charge. That assessment should indicate the potential for savings. In-depth analysis is often done for a fee or a shared savings model. By understanding your options, you are taking the first step in lowering your bills and your carbon footprint while also building resiliency and gaining control of your energy future.

 

 

John Mosher is the vice president of energy solutions at Solect Energy in Hopkinton, MA. John leads Solect’s Energy Storage Division and he can be reached at jmosher@solect.com.

[1] Massachusetts Department of Energy Resources, State of Charge Report, https://www.mass.gov/service-details/energy-storage-study

[2]Jason Deigh, C&I Storage Expected to Grow Threefold…, Feb 17, 2017, Greentech Media: https://www.greentechmedia.com/articles/read/study-sees-big-ci-storage-potential-in-germany-and-u-k#gs.Xj35EQY

[3]Energy Storage Association & Greentech Media, US Energy Storage Monitor: 2017 Year in Review, March, 2018: http://www2.greentechmedia.com/ESM17YIR#gs.9T1PArk

[4]Joyce McLaren & Seth Mullendore, Identifying Potential Markets for Behind the Meter Energy Storage…, Clean Energy Group & National Renewable Energy Laboratory, August, 2017.

[5]DiOrio N, Dobos A, Janzou S. Economic Analysis Case Studies of Battery Energy Storage with SAM. National Renewable Energy Laboratory. https://www.nrel.gov/docs/fy16osti/64987.pdf. Published November 2015.