Thursday, March 29, 2012

Energy use data

Evaluating energy performance requires good information on how, when, and where energy is being used. Collecting and tracking this information is necessary for establishing baselines and managing energy use.

Collect data

The data must be complete and accurate because it will be used for analysis and goal setting. Inventory all energy purchased and generated on-site (electricity, gas, steam, waste fuels) in physical units (kWh, mMBtu, Mcf, lbs of steam, etc.) and on a cost basis. Assemble energy bills, meter readings, and other use data.

Use a Tracking System

A system for tracking performance can range from a simple spreadsheet to detailed databases and IT systems. The following website offers a lot of great advice as well as a "Free Utility Bill Tracking Spreadsheet" for tracking your energy data.


Once you have your yearly data totals it is recommended that you divide the units by 365 to get your average daily usages. This will be very helpful in setting daily targets for energy reductions. The next step is to install real-time energy monitors so that you can track and monitor on a daily basis.

Good Luck!!!

Thursday, March 8, 2012

Energy savings could pay for a new Refrigerator or Freezer!

In with the new...but did you go out with the old?

In the past few years many consumers got federal rebates for new appliances. About 1.7 million rebates were redeemed, and the U.S. Department of Energy estimates these appliances will cut $65 million from electric bills every year.

Great news, right? Sure, if people really follow the adage, "Out with the old, in with the new." But for one in five households, that's not the case. A national survey by the Cooperative Research Network, an arm of the National Rural Electric Cooperative Association, found 19% of homes have two refrigerators; 2% own three or more.

The problem with keeping an old refrigerator is simple: You're not saving money. By sending these "energy hogs" to the basement or garage you jack up electric bills even more.

Appliances already use 13% of your home's electricity, and older appliances drain even more. A refrigerator from 1970s cost $200 more to operate every year than a current model; a 1980 fridge isn't much better, wasting $100 in energy dollars annually.

If you're in the market for a new refrigerator or freezer you should make sure it is Energy Star rated or check the Energy Guide to compare units to make sure you choose an efficient unit. Replacement of older units also offers the opportunity to downsize if your family has downsized over the years.

A newer refrigerator or freezer will use between 1/4 to 1/2 the electricity of an older unit. If you downsize the unit you can save an additional 10-25% on the annual electricity use.

For more information and to calculate energy savings visit the EnergyStar website:

In this example run, upgrading a 19-21 cu.ft. chest freezer will save around $125/year. If you downsize to an 8.8 cu.ft. unit listed in the energy guide above you can save an additional $18/year. A new 8.8 cu.ft. freezer can be purchased for under $300 with rebates, giving you around a 2 year payback with applied energy savings.

Sunday, February 5, 2012

Water Heating

Since water heating can range from 12% to 25% of household energy use lets begin our focus here. It is possible today to cut this cost by 2/3rds with the help of a heat pump water heater. If you are replacing an existing electric water heater you will see a substational savings in your electric usage.  GE claims $320/year.

Currently there are a couple of options:
#1 Installing a GE Hybrid water heater.
This unit uses both resistence elements and a heat-pump to achieve maximum efficiency and better overall performance.

#2 Installing an add-on heat pump to your existing water heater.
While sold as a retrofit...This unit can be difficult to install for the average do-it-yourself person. The retrofit also disables the electric elements so there is a total reliance on the heat-pump for fast recovery and/or problems of placement in an unheated room. It however does a nice job of dehumidification. This manufacture also offers a hybrid unit.

We have one of the air tap units installed in our two person home and have enjoyed the energy savings. It is installed in our basement and has performed beautifully. I did however leave the electric elements hooked up and I connected them to a room thermostat so that if the temperature in the room got below 50 degrees they would be used to speed recovery of  hot water without depleting the space of heat. Not difficult to do but it further discourages a DIY project.

We have also been involved with the installation of the GE unit in a two person home and they have seen substantial energy savings.

- Dehumidification and cooling of room they are in
- Most efficient for 2 person households
- Low wattage requirement over 100% electric
- A must do if you are adding solar to your home and you have an electric water heater

- Savings are based on household size and usages
- Cooling of room they are in
- Long recovery time
- Compressor and fan noise
- High upfront cost
- Cannot be installed in small closed off room

Other ways to cut water heating costs:
- Cold water wash
- Low flow shower heads
- Water heater sizing
- Water heater & pipe insulation
- On demand water heater