Navigant Research Blog

Decoupling H, V, and AC: DOAS and More

— April 14, 2014

Buildings have long been a target for energy efficiency improvements, as they consume a substantial portion of the world’s energy supply (about 40% in the United States).  More recently, the detrimental effects of poorly designed buildings have been established and buildings have been identified as an area to improve the health of occupants.  Though heating, ventilation, and air conditioning (HVAC) systems can be used to accomplish both of these goals, they typically cannot achieve both goals simultaneously.  Conventional approaches to improving indoor air quality (IAQ), such as increasing the ventilation rate or increasing filter efficiency, require using more energy, while increases to energy efficiency (such as improving a building’s seal to reduce infiltration) can have adverse impacts on IAQ.  However, addressing the requirements of heating, ventilation, and air conditioning separately have produced innovative approaches to improve health and reduce costs.

A Flawed Paradigm

Heating, ventilation, and air conditioning are generally lumped into a single system.  Why not?  For the most part, each task requires a box with fans and coils.  Using a single rooftop unit or air handling unit to provide ventilation, filter recirculated air, and produce comfortable temperatures is convenient.  Unfortunately, a single system can have a difficult time maintaining adequate control over disparate conditions.  In practice, adequately addressing IAQ takes a back seat to maintaining space temperature.

In fact, there is evidence that traditional HVAC designs systematically under-ventilate.  Thermostatically-controlled variable air volume (VAV) systems do a poor job of matching airflow to ventilation requirements, particularly in conference and meeting rooms when they are first occupied.  More people in a room increases the generation of both heat and carbon dioxide (CO2).  However, thermostats have a dead-band, an allowable deviation between the actual and desired temperature to avoid short-cycling and simultaneous heating and cooling. As a result, there is a time lag between when the space is occupied and when more than the minimum airflow is delivered.  Moreover, depending on the conditions, the 55°F supply air can offset the temperature rise quickly and return to the minimum position as the CO2 of the space continues to rise.  Theoretically, the minimum damper position should meet the ventilation requirements of a fully occupied room, but improper damper minimums or poor controls integration can lead to under-ventilation.

Separation of IAQ and Thermal Comfort

Decoupling ventilation requirements from thermal comfort through a dedicated outside air system (DOAS) is one way to address this ventilation issue and improve IAQ.  A DOAS provides 100% outside air to a building to meet the building’s ventilation needs.  Typically, it is equipped with some form of energy recovery to precool and dehumidify or preheat and humidify supply air from what is captured from exhaust air.  As a result, the system ensures adequate ventilation and prevents the spread of contaminants between spaces.  Including a DOAS in a building design improves a building’s IAQ by managing it separately from heating and cooling requirements.

However, improving IAQ does not have to be part of HVAC at all.  Introducing filters and outside air into a system that is already designed to move air is convenient, but the same effect can be accomplished by other means.  Adding plants into a space, for instance, can help reduce CO2 and ozone.

The future of IAQ might not be in HVAC, but in the building itself.  Lauzon, a North American flooring manufacturer, has developed a flooring-based solution, called Pure Genius coating, to manage volatile organic compounds (VOCs).  The coating uses photocatalytic titanium dioxide to break down VOCs into water and CO2.  Of course, when maintaining IAQ, converting VOCs to CO2 is a bit like robbing Peter to pay Paul.  However, it shows the advances that materials are making.  Solutions to the current limitations of HVAC equipment might come from outside the mechanical universe rather than from incremental engineering improvements.


Solar Market for Base of Pyramid Not So Pico

— April 14, 2014

In an upcoming report on pico solar lighting products (<10W) and solar home systems (<200W) sold primarily to rural communities in Africa and Asia, I cover the unit sales, revenue, and capacity of these small solar photovoltaic systems globally.  One of the most important trends covered in the report is that pico solar has transitioned from a humanitarian aspiration to big business – more than $100 million in 2014.  Corporate involvement in rural electrification has traditionally come in the form of corporate social responsibility initiatives, but real money is now flowing to solar companies serving the base of the pyramid market.  The success of a number of off-grid solar lighting companies and social enterprises has attracted interest from major corporations such as Panasonic, Schneider Electric, and Philips, as well as funding from investors.  Some of the more notable investments include:

  • In early 2014, d.light raised $11 million in Series C funding from DFJ, Omidyar Network, Nexus India Capital, Gray Ghost Ventures, Acumen Fund, and Garage Technology Ventures.  The company is one of the leading pico solar manufacturers, and has now raised $40 million and sold an estimated 6 million pico solar systems reaching 30 million people.
  • In early 2014, Persistent Energy Partners acquired Impact Energies, a pay-as-you-go, off-grid solar service provider working in West Africa that has reached 30,000 customers since 2011.  The renamed company, Persistent Energy Ghana, installs village solar microgrids and solar home systems.
  • In late 2013, Khosla Impact invested $1.8 million in a Series A round with BBOXX, a U.K.-based company that sells portable solar kits ranging from 7W to 185W and plug-and-play solar systems that range between 2 kW and 4 kW.  The company also provides a mobile pay-as-you-go service enabled by remote battery monitoring, which was the primary interest of Khosla.
  • In 2012, Greenlight Planet, one of the leading designers and distributors of solar light-emitting diode home lights, raised $4 million from Bamboo Finance and Dr. P.K. Sinha, co-founder of ZS Associates.  The investment followed previous financing by Dr. Sinha.  Greenlight Planet has sold more than 1.8 million solar lamps since the company was founded in 2008.
  • In 2012, Barefoot Power, one of the largest pico solar manufacturers, raised $5.3 million from three social investment funds (d.o.b. Foundation, ennovent, and Insitor Fund), existing shareholders (The Grace Foundation and Oikocredit Ecumenical Development Cooperative), and a number of private angel investors.

The full report will be released in the next few weeks.  It will discuss industry market drivers and challenges, and includes more than 20 company profiles and country-specific forecasts from 2014 to 2024.


Honeypots Teach Us About Attackers

— April 11, 2014

Security researchers will try almost anything to find out who is attacking their clients and how.  One of their best-loved and most effective techniques is a honeypot.  First developed about a decade ago, a honeypot is a decoy system or network – a tempting target for attackers that is not really a target at all, but a trap.  The objective is to lure attackers into the honeypot and then watch how they work.  Attackers’ methods are almost like fingerprints; researchers who are familiar with a number of attackers can often identify the attackers simply by watching their step-by-step process of discovery through the honeypot.  Researchers do have other methods as well, such as tracing IP addresses or even fingerprinting the attackers’ browser – adding source code to the attackers’ browser that reveals more about their identity.

Attackers are, of course, aware that honeypots exist, so preparation of an effective honeypot must be extremely detailed.  To set up a honeypot requires a fair bit of planning to make the target look as realistic as possible.  Eventually, the attackers will realize that they’ve been had, so the objective is to keep them in the honeypot as long as possible to gather as much information as possible about their methods and their identity.

One security researcher described one of his honeypots in a talk at the SANS 9th Annual ICS Security Summit.  Kyle Wilhoit of Trend Micro described a scenario in which he set up juicy but fake targets on five continents and then watched them be attacked.   Each was a model of a control system for a small municipality water pump.  Connected directly to the Internet and with insufficient protection, this water pump looked like easy pickings, and it was attacked nearly 100 times.  Again, the attackers were not attacking an actual water pump but were instead sending commands to a simulation of a water pump – the honeypot.

Disturbing Motives

Perhaps most disturbing to me is that most of the attacks that Wilhoit reported were attempted sabotage, not data exfiltration.  Nearly all of my recent research indicates that large-scale persistent attacks against control networks have been data exfiltration for competitive advantage.  In this case, however, data exfiltration attempts were a minority of all attacks.  Even some well-known attack teams supported by hostile nation-states attempted to disable the water pump, not simply exfiltrate its data.  For me, this requires a rethink:  Is all that data exfiltration really just for competitive advantage or are attack plans being prepared?  As ever, only the attackers know, but this one project suggests that there may be more attack planning than has been assumed.

You might think that attackers seeing a control device connected directly to the Internet would say, “Nah, this is too good to be true.”  And then seeing a control device directly connected to the Internet with little or no security – “It just has to be fake, right?”  Sadly, no.  Attackers are accustomed to discovering real systems like this all day long – directly connected to the world and with no protection.

My conclusion is mixed.  Honeypots are an effective tool for learning about our adversaries.  Yet, honeypots work because the unprotected systems that they mimic are commonplace in our industry.


Advanced Energy Is $1.13 Trillion Market

— April 11, 2014

The publication of the Fifth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC), Climate Change 2014: Impacts, Adaptation, and Vulnerability, made headlines recently with a familiar message: The climate is warming, people are causing it, and we are ill prepared to deal with the direct and indirect effects of climate change.

Indeed, it is a grim outlook, but when looking at one indicator not covered in the IPCC report – revenue from deployment of smart energy technologies – there are signs that things are moving in the right direction to reduce emissions.

One group, the Advanced Energy Economy (AEE), is a national association of businesses and business leaders who seek to make the global energy system more secure, clean, and affordable.  The group takes a big tent approach to clean energy.  It is bankrolled by one of the leading advocates and funders for the United States taking a leadership position in deploying clean energy, Tom Steyer.  AEE has identified seven core segments that make up the advanced energy industry: transportation, electricity generation, fuel production, electricity delivery and management, fuel delivery, buildings, and industry.

For the past 2 years, AEE has commissioned Navigant Research to quantify the advanced energy industry market sizes for the United States and globally.  We have identified 41 categories and 80-plus subcategories that meet the AEE definition and put the detailed findings and key trends in the report, Advanced Energy Now 2014 Market Report.  Below are some key findings from the report that illustrate the breadth and depth of technologies that are capable of reducing emissions and U.S. activity in those markets.

Key Findings

  • The global advanced energy market reached an estimated $1.13 trillion in 2013.
  • In the United States, the advanced energy market was an estimated $168.9 billion in 2013 – 15% of the global advanced energy market, up from 11% in 2011.
  • Advanced transportation is booming: Navigant Research forecasts annual plug-in electric vehicle sales will reach approximately 467,000 vehicles in the United States and 80,000 in Canada by 2022 – slightly faster than hybrid electric vehicles sales grew in their first decade.
  • The United States accounted for an estimated 18% of the global solar PV market that approached $100 billion annually in 2013 and far surpassed 100 GW of cumulative installations in 2013.
  • LEDs are expected to be the leading lighting technology over the next decade, with LED lighting products (including lamps and luminaires) in commercial building markets forecast to grow from $2.7 billion in 2013 to more than $25 billion in 2021.

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