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Meter Messenger #120 - Ingersoll Rand Invests in Powerhouse Dynamics
August 15, 2012

Issue #120
July-August 2012

Visit Home Energy

Table of Contents

Ingersoll Rand Invests in Powerhouse Dynamics

What is Power Factor?

Energy Harvesting Devices

Ten Energy Saving Tips

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Ingersoll Rand Invests in Powerhouse Dynamics

Here is a recent press release from Powerhouse Dynamics, manufacturer of the eMonitor™, about their new relationship with Ingersoll Rand's Nexia™ Home Intelligence system:

Boston, MA, August 6, 2012 – Powerhouse Dynamics, the creator of the award winning eMonitor™ energy management system, announced today that Ingersoll Rand, a world leader in creating and sustaining, safe, comfortable and efficient environments, had made a strategic investment in Powerhouse Dynamics. “Consumers are increasingly interested in understanding their energy usage and identifying ways in which they can address controlling their energy usage at a device level. The integration of Powerhouse Dynamics’s eMonitor into Nexia™ Home Intelligence enhances our customers’ ability to control their energy usage through their Nexia systems. Our investment in Powerhouse Dynamics strengthens our partnership, and allows both companies to better achieve their visions for the integrated product line.” said Aine Denari, Director of Strategy for Ingersoll Rand Residential Solutions.

Nexia Home Intelligence, a smart home automation system that leverages the advanced technologies of Trane and Schlage, enables consumers to remotely manage features and functions of their home, including door locks, heating and cooling, video surveillance, lights, shades and energy usage via any Web-enabled computer and most smart phones. The eMonitor uniquely monitors and analyzes all devices that use (or generate) energy in a home or small business at the circuit level, enabling customers to eliminate energy inefficiencies and better manage appliances and equipment. Through the integration, consumers can remotely access their energy usage through the Nexia Home Intelligence platform and leverage the eMonitor’s powerful analytics and alerts engine, while utilizing automation to make smart choices about energy consumption. “We are delighted to welcome a company like Ingersoll Rand as an investor,” said Powerhouse CEO Martin Flusberg. “This investment represents a really powerful endorsement of our products and strategy, and will clearly enable us to build on what has already been a very productive relationship”

The integrated Nexia™ Home Intelligence – eMonitor platform will soon be available through select Trane HVAC dealers and builder partners.

What is Power Factor?

Power factor is a measurement of how efficiently electrical energy is used. Essentially it is nothing more than a measurement of how well synchronized the voltage and current sine waves align with each other. When the power factor is one, or unity, the voltage and current are perfectly aligned which is indicative of a purely resistive load such as a space heater or an incandescent light bulb.

As power factor approaches zero it represents phase a shift of 90 degrees meaning that the current sine wave lags the voltage sine wave by one quarter cycle. This occurs in a purely inductive circuit such as the coils that maintain magnetic fields within an electric motor. Since there is always some energy dissipation due to heat loss, a power factor of zero remains theoretical value. It is technically expressed as a negative value, due to its lagging nature, that can approach zero but never reaches it.

If current leads voltage the power factor is expressed as a positive value between one and zero and the circuit is considered capacitive. This can occur if too much power factor correction in introduced into the circuit or large synchronous motors have field excitation voltages set above rated voltages in industrial applications where an inadequate lagging load exists.

Leading or lagging, power factor represents an inefficient use of electrical energy as its value moves away from unity. Ideally, power factor should be lagging between 95 percent and unity. However, correcting power factor above 80 percent generally has a very poor pay back for larger accounts. Most small residential accounts do not see any payback because they are not penalized for low power factor.

To understand why, we need to look at power factor graphically. It is expressed is the ratio of real power, in kilowatts (KW), to apparent power which is expressed in kilo-volt-amperes (KVA). Apparent power is made up of two components, real power (KW) and reactive power which is expressed in kilo-volt amperes reactive (KVAR). The relationship between these three components can be expressed graphically in what is known as the power triangle.

As mentioned, real power (KW) performs physical work through resistive loads such as heating a burner element or an illuminating an incandescent light bulb. Reactive power (KVAR) is used to sustain magnetic fields such as those found in the coils of electric motors or the power supplies of electronic equipment.

Reactive power does no physical work but circulates current between the generation point and the load. This circulating current places a heavier load on the generator and the distribution system. Click here for more info about the principles of power factor and techniques on how to improve it.

In the residential environment low power factors can occur on bigger motor loads such as HVAC compressors and pool pumps. They are also present on smaller motor loads such as refrigerator compressors, wash machines and dish washer pumps. However, due to the smaller size of these loads, the impact on the whole-house power factor is usually insignificant.

Most residential utility rates in the U.S. do not charge for low power factor, but large commercial and industrial customers can be affected. Residential customers normally pay for kilowatt-hours which is the energy measurement based on real power (KW) only. If a utility rate charges for kilo-volt amp-hours (KVAH) then both real (KW) and reactive (KVAR) power components are included. This means you are billed according to length of the hypotenuse on the power triangle shown above instead of the shorter, real power leg.

Energy Harvesting Devices

Ever had the need to install a switch or sensor but found wiring or batteries to be a hindrance? Well, there is a new energy harvesting technology that has been developed by EnOcean that powers wireless switches and sensors from ambient energy.

This means switches are powered from the motion that actuates them. Occupancy sensors extract ambient light through embedded solar films when the lights are on. HVAC dampers can be controlled by producing electricity from the differences in air temperature around them. Very low energy wireless transmitters send a signal from the switch or sensor to a receiver that turns a device or appliance on or off.

The concept behind energy harvesting devices is simple. Switches and sensors reside in an environment of ever shifting energy states because that is what they control. By harvesting a very small amount of energy from this ever changing state, these low power devices can generate the wireless control signals needed to turn things on and off.

The technology has been around for a few years in the commercial and industrial world but is only starting to enter the residential market. The primary reason is cost. A kinetic powered switch may cost $40 as compared to a couple of dollars for a hard-wired switch at a local home center. However, wiring costs can be lowered by 15 percent on a new home or 50 to 75 percent if remodeling according to EnOcean's president, Jim O'Callaghan.

The beauty to installing these devices is that you simply place them in the wall where you want them. There are no wires to run and no batteries to replace when they stop working.

Ten Energy Saving Tips

1. Put your ceiling fan to work on these warm summer days. The moving air helps to keep you cool - enough so that you can bump up your thermostat a couple of degrees and most likely not notice the difference. The ceiling fan draws much less power then the compressor motor in your air conditioner.

2. Consider an attic fan if you do not already have one. They draw the hot air out of the attic so the insulation in your ceiling has a smaller temperature differential to deal with. The result, less air conditioner run time.

3. LED lighting is becoming more and more affordable. When you consider the huge energy savings over conventional incandescents and the extremely long bulb life, LED's are really starting to make sense. Check out our incandescent lighting comparison page for more details.

4. Make sure bathroom fans are turned off when you are done using them. A bathroom fan left on for eight hours can expel the entire volume of air contained in a 2500 square foot home. This forces the air conditioner to work harder to cool the replacement air.

5. If your home has unused attic space beneath the roof, consider blowing insulation into the area, A one foot deep blanket will have an R-value of around 60 as compared with typical 6 inch batts that are rated at R-30.

6. Be sure to keep drapes pulled on west facing windows during these hot summer afternoons. It keeps heat load from building up in the room and slows the fading of carpet and fabrics.

7. When preparing a meal for just one or two people consider using a toaster oven or microwave instead of the oven or range. Remember that you pay twice for that energy. You pay for the energy to heat your cooking appliance and you pay for it again when your air conditioner has to extract the excess heat from the room.

8. Thermostat set points cost money. For every degree you lower your thermostat below 78 degrees, cooling costs go up 3 to 5 percent. The same is true in winter for heating costs above 68 degrees.

9. Does your utility offer a time-of-use rate? It may or may not benefit you. If you can shift load to off-peak hours such as your air conditioner, pool pump or clothes dryer it may be a good idea. If you are home during the day with the A/C on and running most appliances during the peak period it may be more economical to stay on a flat rate.

10. If you have a programmable thermostat, be sure it is programmed to your schedule - even if it means digging out the manual to refresh your memory on how to do so. Surprisingly. a large percentage of these devices are never programmed and are just left to run at less efficient default settings.

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