What are Net Zero Energy Buildings (NZEBs) and why do they matter? NZEB guru Tim Wentz shares his ideas at a meeting of building technology experts. Meeting sponsored by ITT (Now Xylem) RCW.

Tim Wentz is a registered professional engineer, a LEED Accredited Professional and a member of the faculty of the University of Nebraska-Lincoln’s Construction Management program. He received MCAA’s 2009 Distinguished Service Award and is an ASHRAE fellow.

This from a new release from Pike Research:

"Because commercial buildings consume roughly 23% of all electricity globally, the automation systems that ensure efficient performance are a critical part of energy management.  Until the mid-1990s, modern building automation consisted of little more than individual systems with simple control panels for switches, timers, and alarms.  Today, the market for commercial building automation systems is in the midst of revolutionary change in terms of technology and utility.  In the last several years, the focus has shifted from an individual system view to a more holistic view so that the “building system” can be defined to include virtually any device or data source within the building.  The amount of data created by automation systems can be overwhelming, but real competitive and economic value exists in using the data to monitor performance and uncover trends.  According to a new report from Pike Research, the market for commercial building automation systems will double over the next decade, increasing from $72.5 billion in 2011 to $146.4 billion by 2021."

The complete release is here: http://www.pikeresearch.com/newsroom/global-revenues-for-commercial-building-automation-systems-will-reach-146-billion-by-2021

Timing the announcement with the AHR show this week in Chicago, Danfoss has introduced the VLT® HVAC Basic Drive - a small, full-featured variable speed drive that promises reliable, low-cost HVAC performance for basic fan and pump operations.

“In some fan and pump operations advanced drive features are unnecessary and, because they are superfluous, simply add to overall costs.  The VLT HVAC Basic Drive is an ideal solution that strikes the optimum balance between price and variable speed drive performance in these straightforward HVAC installations,” says Ed Smith, a company representative.

VLT HVAC Basic Drives minimize wear on HVAC equipment and maximize system up-time, while reducing HVAC system operating costs up to 15%. 

The company says that the VLT HVAC Basic Drive is the most compact drive in its class and with its specifications to reduce panel space requirements. Numerous built-in features reduce, and in some applications may even eliminate, the need for additional external equipment such as gateways, PI controllers and PLCs.  An Automatic Energy Optimizer function reduces energy consumption by up to 15%, while “sleep mode” functionality can help further reduce operating costs and extend drive life.  Bypass frequencies minimize operating noise, vibration and resonance issues.

VLT HVAC Basic Drives also feature a “start up wizard” that makes drive set-up fast and simple, and easy tool access further aids fast and effective commissioning and operation.  A robust single-piece enclosure provides reliable, maintenance-free operation in ambient temperatures up to 50 degrees C, with no external cooling required.  A unique cooling concept provides problem-free performance, even in harsh environments, without forced air flowing over the electronics.

What is SmartGrid?

Testing a VFD for energy efficiency.

Last week members of a team at Oil field giant Baker Hughes were awarded a patent for a drive-controlled downhole pump system configuration where oil well performance is optimized through the use of voltage and torque sensing and control to precisely time the restart of a well when an interruption has occurred. The result is a higher performing well.

While the patent is wide ranging (as many are), the essential benefit of the technique is to make incremental improvements to system availability and to lower the time between failures across a wide range of scenarios. This would not be possible without the drive.

For example, according to the patent, "...if the pump system has enough torque to restart at the identified speed, it can be immediately restarted. If the system does not have enough torque to restart immediately, the drive continues to match the motor speed until the motor speed falls below a threshold level at which the pump system has sufficient torque to restore forward rotation of the pump and support the column of fluid in the well. The pump can then be restarted. Alternatively, the drive can continue to match the motor speed until it is determined that the motor has stopped, at which point the pump can be restarted. It should be noted that, if the drive sweeps through the range of frequencies at which the pump motor may be spinning and does not detect any drops in output current, it can be assumed that the pump has stopped spinning and can be restarted normally."

The point is that we've reached an exciting time in the development of drives. System engineers understand the base economics, the usefulness and the potential of drives, and are now using them as tools to improve overall system performance and make machines more flexible and productive.

So it's not always just about energy.

For those who would care to learn more about the Baker Hughes patent, here are some highlights.

The application challenge is explained in the "related art" section:

Crude oil is typically produced by drilling wells into oil reservoirs and then pumping the oil out of the reservoirs through the wells. Often, the oil is pumped out of the wells using electric submersible pumps. Electrical power is provided to electrical drive systems at the surface of the wells and these drive systems provide the required electrical power to the downhole pumps.

While downhole pumps are designed to operate continuously, they are subject to interruptions that can result from a number of different causes. For example, changes in well conditions (e.g., the appearance of gas in an oil well) may cause the pump to stop operating. Interruptions or variations in the power supplied to a pump's drive system may also cause operation of the pump to be interrupted. Even if these interruptions in the operation of the pump are relatively short, they may nevertheless be very disruptive, particularly when the pumps are submersible pumps operated in deep wells.

These interruptions may be very disruptive because submersible pumps, which must fit in a well and must therefore be long and narrow, have very little inertia. Consequently, when there is a change in conditions which causes an interruption, these pumps slow down or stop very quickly in comparison to pumps which have more inertia, such as surface pumps. The deceleration of the pump is even more pronounced in deep wells due to the large fluid column above the pump. Normally, when the operation of the pump is interrupted for longer than about half a second, the pump will have begun to spin in reverse.

Typically, there is some speed below which the pressure produced by the pump is insufficient to support the column of fluid. When the rotation of the pump falls below this speed, the fluid starts to fall back through the well and through the pump, dramatically increasing the torque required to resume forward rotation of the pump. While it is possible to match the speed of the pump motor, slow its reverse spin and start it spinning forward again, this often requires a great deal of torque. The torque that can be generated by the pump system may be limited by such factors as the output of the drive for the pump motor, the impedance of the cable carrying the power downhole, etc., so restarting the pump motor may require more torque than the system can generate. It is therefore typically necessary to stop the pump and wait for the column of fluid to drain from the well before the pump can be restarted. The time required for the fluid column to drain back into the formation may take a few minutes in some cases, while in other cases it may take more than an hour.

Normally, when it is necessary to restart a pump, an operator waits for a predetermined period and then restarts the pump. The wait period is typically determined by adding the amount of time necessary for the fluid to completely drain from the well and a safety margin (for example, an additional 25%.) Because each well may normally produce hundreds or even thousands of barrels of oil in a day, the cost associated with the delay between the pump stopping and being restarted can be very high. There is therefore a need to minimize the delay between the time the pump stops and the time the pump is restarted.

And the drive-enabled solution is explain in the summary of the invention (although there are many disclosures. We've just highlight one.)

This disclosure is directed to systems and methods for using variable speed drives to restart downhole submersible pump motors that solve one or more of the problems discussed above. In one particular embodiment, a downhole electric submersible pump deployed in a well is controlled using a variable speed drive. The variable speed drive includes a control system which is configured to detect interruptions in the operation of the pump system. If the control system detects a power interruption or some other interruption that requires the restart of the pump motor, the control system determines the reverse rotational speed of the pump motor and restarts the motor when this speed is sufficiently low. In this embodiment, the control system is configured to reduce the output voltage of the variable speed drive and sweep through a range of output frequencies to determine the frequency at which the current drawn by the motor is lowest. This is the frequency at which the apparent impedance of the motor is highest, indicating that the frequency of the variable speed drive's output matches the speed of the motor. The reverse rotational speed of the motor is known from this frequency, so the control system determines whether the speed is low enough that the pump system has sufficient torque to restart. If the speed is low enough, the motor is restarted. Otherwise, the control system continues to monitor the speed of the motor and restarts the motor after its speed is determined to be sufficiently low.

Is this where home automation is going?

“Variable speed motor control in home appliances holds the key to significant energy savings. However, the design of the electronic control unit is complex. At the same time, designers must achieve high performance at relatively low cost for the high-volume market, desiring components with small form factors and a high level of integration to simplify manufacturing,” said Alberto Guerra, Vice President of International Rectifier's (IR’s) Energy Saving Products Business Unit.

Guerra's comments come as the company announces that its IRMCK171 one-time programmable ROM-based monolithic mixed-signal IC for sensorless sinusoidal motor control of appliances meets the standards of IMQ (Italy) Annex R of IEC 60335-1 Edition 4.2 – Class B software requirements.

The new certification allows even further simplification and acceleration of the design process for home appliances using the IRMCK171 by reducing elements of the software testing process. The IMQ certification also enables customers to more easily obtain the safety standard of their appliance products which is a mandatory requirement for today’s home appliance goods.

Guerra continúes, “IR’s iMOTION platform consists of a development system, mixed-signal analog chipsets and power stages, that when co-designed together, simplify motor control designs and bring energy-efficient, cost-effective solutions to market faster. This platform provides a compelling argument for manufacturers to adopt permanent magnet variable-speed motor drives in home appliances, and with the IRMCK171, the design cycle and safety certification process can now be accelerated even further.”

The IRMCK171, part of the iMOTION™ integrated design platform for variable speed motor control, incorporates IR’s patented Motion Control Engine (MCETM), an algorithm editor that eliminates coding.  A co-integrated 60MIPS, 8-bit, 8051 microcontroller enables application layer software development, operating almost independently of the MCE and does not compete for system resources such as interrupts or internal registers. The embedded Analog Signal Engine (ASE) integrates all the signal conditioning and conversion circuits required for single current shunt, sensorless control of a permanent magnet motor.

An electrician explains the basic operation of an ABB VFD.

Siemens boasts about its automation offer and how it increases productivity and energy efficiency in this promotional video.