HomeMy WebLinkAboutLakeview Lodge Minto, AK Energy Modeling Analysis 2013
Date: August 19, 2013
To: Minto Village Council
From: Jared Temanson, NREL
Subject: Lakeview Lodge Energy Modeling Analysis
Dear Minto Village Council:
The attached analysis evaluates the seven energy conservation measures (ECMs) proposed by the
Interior Regional Housing Authority for Lakeview Lodge. The analysis shows the seven ECMs
resulting in a combined energy savings of almost 23% over the current baseline. This equates to
an annual cost savings of roughly $18,000.
Feel free to call or email if you would like to discuss this analysis further or if you have any
additional questions.
Sincerely,
Jared Temanson
National Renewable Energy Laboratory (NREL)
Integrated Application Center
Jared.Temanson@nrel.gov
303-384-7452
Executive Summary
Eight energy conservation measures (ECMs) were analyzed using an eQUEST energy model of
Lakeview Lodge (Lodge) in Minto, Alaska. The model was created and calibrated using
provided utility and building information. The baseline electricity consumption for the Lodge
was 50,155 kWh per year and the heating fuel consumption was 10,008 gallons per year,
bringing the village’s total energy bill to just over $80,000. The combined ECMs, listed below,
reduce the Lodge’s total electric consumption by 11,026 kWh per year and the heating fuel
consumption by 2,289 gallons per year.
The eight ECMs include:
1. Floor insulation
2. Wall insulation
3. Roof insulation
4. Energy efficient doors
5. Energy efficient windows
6. LED lighting
7. Heating system upgrade
8. Combined ECM1 to 7
A cost-reduction summary of the ECM analysis for Lakeview Lodge is given below:
Description Energy Cost Reduction
($)
Percent Cost Savings
(%)
ECM 1: Floor insulation $ 1,814 2.2%
ECM 2: Wall insulation $ 2,514 3.1%
ECM3: Roof insulation $ 2,641 3.3%
ECM4: Energy efficient doors $ 303 0.4%
ECM5: Energy efficient windows $ 897 1.1%
ECM6: LED lighting $ 4,468 5.5%
ECM7: Heating system upgrade $ 7,029 8.7%
ECM8: Combined ECM1-7 $ 18,345 22.6%
Discussion
ECM analysis results show the energy/cost savings of the combined ECMs at 22.6% or $18,345
per year. With an estimated project cost of $249,575, this combination of measures has a simple
payback of 13.6 years.
The majority of ECMs are building shell improvements, which are essential given the present
condition of the building and the extreme Alaska Climate. The heating system upgrade shows the
most significant savings. Original building ventilation relies on infiltration through envelope
leakage. Building shell improvements will significantly reduce building leakage. NREL
recommends a blower door test to measure airtightness and assess whether a mechanical
ventilation system may be required for the tighter envelope to meet indoor air quality (IAQ)
requirements. If mechanical ventilation is required, the village should consider an energy
recovery ventilator.
Electricity and heating fuel are very expensive at the location. After energy efficiency
improvements, renewable energy technologies such as wind, solar and biomass may be
economically feasible for this building. Further analysis of the renewable energy potential at this
site is recommended.
Building Information
Lakeview Lodge is a multipurpose community building in Minto Alaska, built in the early
1980s. The building is used all throughout the day for various purposes, including school
lunches and a senior lunch program. The building is approximately 12,000 ft2, with
approximately 2,000 ft2 dedicated to office space. Photographs of the actual building are shown
in Figure 1.
The offices are utilized Monday through Friday all year long, typically from 8am - 5 pm. Elders
are served lunch Monday through Friday all year long. Student lunches are served throughout
the school year – the end of August until mid-May. There are two rooms that are rented out all
year long to two Minto residents.
The heating system is a hydronic glycol loop with baseboard. The lodge has a single 400,000
BTU boiler and an indirect hot water tank. There is no cooling system in this building. There is
no air circulating or HRV setup anywhere in the building. All ventilation comes from the leaky
windows, leaky crawl space and leaky doors. The building is on a manual thermostat
control. There is no auto thermostat that reduces the temperature when not in use.
There are total of 125 2-lamp T-8 fixtures. They are manually controlled through on-off
switches.
Figure 1: Photographs of Lakeview Lodge
Energy Model
An energy model of the Minto Lodge was created in eQUEST, an hourly building simulation
model. Fairbank’s TMY (typical meteorological year) weather data was used in the simulation.
Electricity rate of $0.52/kWh and heating fuel rate of $5.5/gallon were used. During this
analysis, the model was calibrated with provided utility information. Calibration results are
presented in Table 1. A graphic representation of the energy model of the Minto Lodge is shown
in Figure 1.
Figure2: A graphic representation of the energy model
Table 1: Model calibration results with utility information
Energy Conservation Measures Analysis
Eight energy conservation measures (ECMs) were analyzed. The eight ECMs include:
1. Floor insulation
2. Wall insulation
3. Roof insulation
4. Energy efficient doors
5. Energy efficient windows
6. LED lighting
7. Heating system upgrade
8. Combined ECM1 to 7
The following tables detail how each ECM impacts the Lodge’s total energy consumption and
the cost savings that it yields.
from billing from model Diff (%)
Electricity (kWh/yr)51,389 50,155 2%
Heating Fuel (gallon/yr)9,855 10,008 -2%
ECM 1 – Floor insulation
The measure was modeled by changing the floor insulation values from a baseline of R-15 to a
proposed insulation of R-56. Baseline floor insulation was assumed per a prescriptive energy
code for the building vintage. The results from the analysis are given in the table below.
ECM 2 – Wall insulation
The measure was modeled by changing the wall insulation values from a baseline of R-15 to a
proposed insulation of R-37.5. Baseline wall insulation was assumed per a prescriptive energy
code for the building vintage. The results from the analysis are given in the table below.
ECM 3 – Roof insulation
The measure was modeled by changing the roof insulation values from a baseline of R-20 to a
proposed insulation of R-100. Baseline roof insulation was assumed per a prescriptive energy
code for the building vintage. The results from the analysis are given in the table below.
Description
Electricity
Consumption
(kWh/yr)
Electricity
Cost
($/yr)
Heating Fuel
Consumption
(Gallon/yr)
Heating Fuel
Cost
($)
Total Cost
($)
Cost Savings
($)
Percent
Cost
savings
(%)
Baseline 50,155 26,181$ 10,008 55,044$ 81,225$ --
ECM 1: Floor insulation 50,157 26,182$ 9,678 53,229$ 79,411$ 1,814$ 2.2%
Description
Electricity
Consumption
(kWh/yr)
Electricity
Cost
($/yr)
Heating Fuel
Consumption
(Gallon/yr)
Heating Fuel
Cost
($)
Total Cost
($)
Cost Savings
($)
Percent
Cost
savings
(%)
Baseline 50,155 26,181$ 10,008 55,044$ 81,225$ --
ECM 2: Wall insulation 50,154 26,180$ 9,551 52,531$ 78,711$ 2,514$ 3.1%
Description
Electricity
Consumption
(kWh/yr)
Electricity
Cost
($/yr)
Heating Fuel
Consumption
(Gallon/yr)
Heating Fuel
Cost
($)
Total Cost
($)
Cost Savings
($)
Percent
Cost
savings
(%)
Baseline 50,155 26,181$ 10,008 55,044$ 81,225$ --
ECM3: Roof insulation 50,154 26,180$ 9,528 52,404$ 78,584$ 2,641$ 3.3%
ECM 4 – Energy Efficient Doors
The measure was modeled by changing the door insulation values from a baseline of R-2 to a
proposed insulation of R-5.3. Baseline door insulation value was assumed per a prescriptive
energy code for the building vintage. The results from the analysis are given in the table below.
ECM 5 – Energy Efficient Windows
The measure was modeled by changing the window U-value from a baseline of U-0.32 to a
proposed U-value of U-0.29 (R-3.4). Baseline window U-value was assumed per a prescriptive
energy code for the building vintage. The results from the analysis are given in the table below.
ECM 6 – LED Lighting
The measure was modeled by reducing the lighting power of fluorescent lamps from a baseline
by 40% for LED lighting. Baseline lighting power was calculated based on the provided
information. The results from the analysis are given in the table below.
Description
Electricity
Consumption
(kWh/yr)
Electricity
Cost
($/yr)
Heating Fuel
Consumption
(Gallon/yr)
Heating Fuel
Cost
($)
Total Cost
($)
Cost Savings
($)
Percent
Cost
savings
(%)
Baseline 50,155 26,181$ 10,008 55,044$ 81,225$ --
ECM4: Energy efficient doors 50,155 26,181$ 9,953 54,742$ 80,922$ 303$ 0.4%
Description
Electricity
Consumption
(kWh/yr)
Electricity
Cost
($/yr)
Heating Fuel
Consumption
(Gallon/yr)
Heating Fuel
Cost
($)
Total Cost
($)
Cost Savings
($)
Percent
Cost
savings
(%)
Baseline 50,155 26,181$ 10,008 55,044$ 81,225$ --
ECM5: Energy efficient windows 50,155 26,181$ 9,845 54,148$ 80,328$ 897$ 1.1%
Description
Electricity
Consumption
(kWh/yr)
Electricity
Cost
($/yr)
Heating Fuel
Consumption
(Gallon/yr)
Heating Fuel
Cost
($)
Total Cost
($)
Cost Savings
($)
Percent
Cost
savings
(%)
Baseline 50,155 26,181$ 10,008 55,044$ 81,225$ --
ECM6: LED lighting 39,131 20,426$ 10,242 56,331$ 76,757$ 4,468$ 5.5%
ECM 7 – Heating System Upgrade
The measure was modeled by changing the boiler efficiency from a baseline of 75% to a
proposed efficiency of 86.9%. Baseline boiler efficiency was assumed per a prescriptive energy
code for the building vintage. The results from the analysis are given in the table below.
ECM 8 – Combined ECM1-7
The measure was modeled by combining all changes of ECM1 to 7. The results from the analysis
are given in the table below.
Description
Electricity
Consumption
(kWh/yr)
Electricity
Cost
($/yr)
Heating Fuel
Consumption
(Gallon/yr)
Heating Fuel
Cost
($)
Total Cost
($)
Cost Savings
($)
Percent
Cost
savings
(%)
Baseline 50,155 26,181$ 10,008 55,044$ 81,225$ --
ECM7: Heating system upgrade 50,155 26,181$ 8,730 48,015$ 74,196$ 7,029$ 8.7%
Description
Electricity
Consumption
(kWh/yr)
Electricity
Cost
($/yr)
Heating Fuel
Consumption
(Gallon/yr)
Heating Fuel
Cost
($)
Total Cost
($)
Cost Savings
($)
Percent
Cost
savings
(%)
Baseline 50,155 26,181$ 10,008 55,044$ 81,225$ --
ECM8: Combined ECM1-7 39,129 20,425$ 7,719 42,455$ 62,880$ 18,345$ 22.6%