1. Charlie_Rogers
   Board Secretary
   

   Energy Savvy recently requested I answer a customer's question about Home Monitoring Systems. See below for my response. Let me know if you have other ideas.

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   There are a few options to meet this need. Currently there are 3 major home energy monitoring systems on the market:

   1. Power Cost Monitor <http://www.powercostmonitor.com/>
   2. Energy Detective <http://www.theenergydetective.com>
   3. Black and Decker Power Monitor <http://www.blackanddecker.com/energy/>

   Each of these are designed mainly to monitor whole house energy use in real time. You can enter your unique utility rate structure and most of these devices will calculate your predicted utility bill (and show your real time consumption in dollars instead of kWh). Each costs between $100 and $200. A certified electrician should install the monitor (that goes into the electrical panel) and would take them about an hour's worth of labor.

   Out of the three, the only monitor that can give circuit specific information is the Energy Detective. To do this, you will need to purchase additional current sensors. A full package including the monitor, display and 4 current sensors (one for the main line and three for the circuits of your choice) costs $455.80! Additional sensors beyond that cost $84.95.

   There exists equipment that can monitor all circuits simultaneously, but it is even less affordable for homeowners. This equipment is better suited for an electrician contractor who can conduct a comprehensive load analysis. There are energy efficiency minded electricians who can offer this service for a fee. They will also inspect the panel for lose connections, hot wires, and other safety issues. This will, however, only give you a snapshot of electrical usage.

   Another device that can help is the Kill-o-Watt meter. It can monitor the power consumption of an individual appliance. It costs about $50. It is restricted to 110v and there is no similar product for 220v appliances such as stoves and clothes dryers.

   There is also one useful (and free) database for estimating electrical usage of the most power hungry appliance in most houses--the refrigerator.

   <http://www.kouba-cavallo.com/refrig1.html>

   All that said, is it worth it? Is all this gadgetry another fancy tool to show off (Google now makes a tool that allows you to view your Energy Detective readings online)? Another thing to buy and a way for a company to make another buck off you? Does it distract us from real, strategic energy savings?

   Most of the Home Monitoring Systems companies claim multiple studies show these devices will help you save 10-20% off your electrical bill. This is misleading. There has only been one study conducted using the Power Cost Monitor. It was published in 2006 by Dean Mountain a professor of economics at the McMaster Institute for Energy Studies in Hamilton Ontario. The study was completed in Ontario and analyzed 500 households. It concluded that houses heated with electricity demonstrated an average reduction in usage by 1.2%. Houses heated by other means showed an average reduction of 8.2%.

   These tools may be fun to learn about how energy is consumed in your house. If your family tends to leave appliances and lights on, your household may really benefit from this education. But it could also benefit from motion-sensor light switches, energy star appliances and smart surge protectors.

   In general, it seems most people would be better off first spending their money on real measures that reduce usage: Air seal your house; add insulation to your attic, walls and floors; buy Energy Star rated appliances (especially for fridges and washing machines); upgrade your heating system; etc. If you're not sure where to start, consider hiring an energy auditor who can provide you with a comprehensive, prioritized list of to-do's that are specific to your home.

   Posted 8 months ago #

2. Charlie_Rogers
   Board Secretary
   

   After lunch I thought of a few more points to add:

   * There are some houses that have an unusually high base-load. This can be determined by analyzing billing history. These houses would benefit the most from a monitoring system.

   An aside: In one mobile home I audited I found this to be the case and I recommended an electrician do some line testing to investigate further. The electrician found nothing. The HVAC contractor who came to clean and tune the electric furnace found one of the furnace breakers (in the panel) was shorting, slowly melting and presented an immediate fire hazard. He replaced the breaker and the problem was solved.

   * In the Canadian study, the average reduction in usage of non-electric heated houses (8.2%) is greater than average reduction in electrically heated houses (1.2%) not because there were greater savings, but because the savings represented a larger proportion of the house's electrical use.

   * Another point of argument in favor of home monitoring systems may be that they allow homeowners to stay on top of changes in their house. Maintenance is way too often overlooked and these systems could help identify when mechanical systems fail. It should also be noted that one's utility bill can serve the same purpose. Some utilities' websites also provide ratepayers with daily usage data as well.

   Posted 8 months ago #

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