HERS Example
| HERS Scale
|
| Points |
Stars |
Energy Consumption |
| 0-39 |
* |
More than 3 x the reference home |
| 40-59 |
** |
More than 2 x and up to 3 x the reference home |
| 60-79 |
*** |
More than 1 x and up to 2 x the reference home |
| 80-85 |
**** |
30% less and up to 60% less than reference home |
| 92-100 |
****+ |
60% less and up to 100% less than reference home |
| Table 1. This
scale, developed by the National Home Energy Rating Systems Council, is based
on the U.S. Department of Energy's national voluntary guidelines for HERS
uniformity. For rating purposes, a subject home is compared to a "reference
home," which scores 80 points on a 100-point scale with a rating of four stars.
Every 5% decrease in the annual energy costs between the subject home and the
reference home increases the subject's home score by 1 point from 80 points.
Meanwhile, every 5% increase reduces the score by 1 point from 80 points. Note:
your state may use a different HERS and scale. |
| HERS Report
|
An Energy-Effieicnt Home
Estimated Annual
Energy Use & Costs |
| Description |
|
Energy Use |
Energy Cost |
| |
Space Heating |
23.9% |
21.90 Mbtu |
$110.33 |
| Space Cooling |
33.2% |
30.41 Mbtu |
$588.61 |
| Water Heating |
16.6% |
15.23 Mbtu |
$76.14 |
| Other Energy Uses |
26.3% |
24.12 Mbtu |
$272.36 |
| Total |
100% |
91.66 Mbtu |
$1,047.44 |
Source: National
Home Energy & Resources Organization, Inc.
*Mbtu= 1,000,000 Btu
Table 2. Based on the HERS scale in Table 1 (above), this brand new,
energy-efficient, 3,585 square-foot home in Houston, Texas, received a score of
89 points and five stars. The home features double-glazed windows, a 40-gallon
natural gas water heater, a natural gas central air furnace, and an electric
central air conditioner. A programmable thermostat controls the furnace and air
conditioner. |
A Home In Need of
Energy-Efficient Improvements
Annual Energy Use & Costs
without Improvements
|
| Description |
|
Energy Use |
Energy Cost |
| |
Space Heating |
78.5% |
233.44 Mbtu |
$1,141.43 |
| Space Cooling |
10.5% |
29.27 Mbtu |
$645.77 |
| Water Heating |
6.2% |
17.60 Mbtu |
$88.02 |
| Other Energy Uses |
4.9% |
13.92 Mbtu |
$265.04 |
| Total |
100% |
284.79 Mbtu |
$2.140.26 |
Source: National
Home Energy & Resources Organization, Inc.
*Mbtu= 1,000,000 Btu
Table 3. Based on the HERS scale in Table 1 (above), this 1,475 square-foot
home in Tulsa, Oklahoma, received a score of only 21 points and one star. The
home has single-paned windows, a 40-gallon natural gas water heater, natural
gas central furnace, and an electric central air conditioner. A manual
thermostat controls the furnace and the air conditioner. Equivalent
carbon-dioxide emissions of 31.01 tons per year. |
| Estimated Annual Energy Use
& Costs with Improvments |
| Description |
|
Energy Use |
Energy Cost |
| |
Space Heating |
58.7% |
63.99 Mbtu |
$326.90 |
| Space Cooling |
12.4% |
13.46 Mbtu |
$291.73 |
| Water Heating |
16.2% |
17.60 Mbtu |
$88.02 |
| Other Energy Uses |
13.92% |
13.92 Mbtu |
$265.04 |
| Total |
100% |
284.79 Mbtu |
$971.69 |
Source: National
Home Energy & Resources Organization, Inc.
*Mbtu= 1,000,000 Btu
Table 4. The homeowner will save more than 50% annually in energy costs if
recommended energy-effiecient improvements are made to the house in Table 3
(above). These improvements include sealing heating and cooling ducts,
caulking, weatherstripping, installing a more energy-efficient central cooling
system (10 SEER), installing more insulation in the crawlspace/basement and in
the ceiling, and insulating hot water pipes. Payback for the improvements is
estimated at a little more than 4 years. Equivalent carbon-dioxide emissions of
10.88 tons per year. |
|
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