Transcript Transformer De-Energizing & Dairy Plate Heat Exchanger Standard Protocol Proposal Presentation to the RTF February 20, 2013

Transformer De-Energizing &
Dairy Plate Heat Exchanger
Standard Protocol Proposal
Presentation to the RTF
February 20, 2013
Protocol History
• Adopted “deemed calculator” versions in 2002
• Savings Guidelines adopted 6/1/11 which
removed deemed calculator category
• Cascade Energy awarded contract in 2012 to
convert deemed calculators to Guidelines
compliant Standard Protocols
• Presented draft protocols at Oct. & Nov. 2012
RTF meetings
Protocol History
• Received feedback at meetings on likely path
– Small Saver recommended at Nov. RTF meeting for
both protocols
• Tabled decisions until updated Savings
Guidelines were adopted to allow for Small
Saver Standard Protocols
• Mike Baker reviewed for compliance with
updated 12/11/12 Savings Guidelines
• Presenting revised proposal today
Standard Protocol
TRANSFORMER DE-ENERGIZING
Protocol Summary
Eligibility
•
•
•
•
Baseline
Existing energized transformer with periods of no-load
Upgrade
De-energize the transformer for periods of no-load
Liquid-filled or dry-type transformers
Single phase between 3 kVA – 167 kVA
Three phase between 15 kVA – 1,000 kVA
Low voltage (<= 600V)
Best Practice Savings Estimate
1. Determine no-load loss by measuring the power of the transformer when it is energized, but does not have an
electrical load.
2. Collect transformer nameplate data (type, voltage, phase, capacity rating).
3. Determine the number of hours per year the transformer is de-energized based on utility record of date(s) of deenergization and date(s) of re-energization.
4. Savings are calculated as the product of hours of de-energization and no load power draw.
5. Savings are to be determined in this manner each year the transformer is de-energized.
Simplest Reliable Savings Estimate
1. Determine no-load loss by:
a) Default rated capacity by utilizing default NEMA TP-1 transformer efficiency ratings
b) Alternately, use manufacturer published no-load loss or power measurement
2. Remaining steps follow the Best Practice.
RTF feedback from last meeting
• Using NEMA tables vs. field data collection
– Field data collection is costly, and savings are not
justified given the expense
– Regionally representative default table would be
better however not worth the cost to obtain given
small savings
– Only two utilities run xfmr de-energizing programs
– Keep NEMA table as-is and realize protocol is a
small saver for the region
Protocol changes since November
• Cleaned up verbiage to clarify definitions,
delivery verification and data collection
characteristics
• Biggest change is restructuring of simplest
reliable method to use NEMA default table
– Previously had manufacturer rating as primary
collection method, default table as secondary
– Guidelines require alternate methods to be of
sufficient or better reliability
RTF Proposed Motion:
“I _________ move that the RTF approve the
Transformer De-Energizing Standard Protocol and
assign it to a “Small Saver” category with “Active”
status and a sunset date of February 20, 2017.”
Standard Protocol
DAIRY HEAT EXCHANGER
Process Flow Diagram
T
T
T = temperature measurement
Measure Definition
Eligibility
Plate and frame heat exchanger
Retrofit only
Water is the cooling fluid, and has constant flow
known cooling water flow rate, and inlet and outlet temperatures, or alternately,
known milk outlet temperature
Baseline
Mechanical refrigeration system to cool milk
May or may not have existing milk pre-cooler
Upgrade
Add milk-to-water plate and frame heat exchanger or replace existing.
Simplest Reliable Method
Same equations as Best Practice, different data collection
Simplest Reliable method
• 𝑇𝑚−𝑜𝑢𝑡 can be impossible to measure.
• Easier to measure water heat gain rate than milk heat loss for baseline and
post water-cooled HXR.
𝑄𝑏𝑎𝑠𝑒𝑙𝑖𝑛𝑒 𝐵𝑇𝑈/ℎ = 𝑚𝑤 ∗ 𝑇𝑤−𝑜𝑢𝑡−𝑏𝑎𝑠𝑒𝑙𝑖𝑛𝑒 − 𝑇𝑤−𝑖𝑛
• Need to measure transfer pump runtime per quantity of milk
𝐸𝑛𝑒𝑟𝑔𝑦𝑏𝑎𝑠𝑒𝑙𝑖𝑛𝑒 𝐵𝑇𝑈/𝑦𝑟
= 𝑚𝑚 ∗ 𝐶𝑝 ∗ 𝑇𝑚−𝑖𝑛 − 𝑇𝑓𝑖𝑛𝑎𝑙
𝑄𝑏𝑎𝑠𝑒𝑙𝑖𝑛𝑒 ∗ t 𝑝𝑢𝑚𝑝 ∗ 𝑚𝑚
−
𝑚𝑡𝑒𝑠𝑡
Total heat rejection
• Same equations for post HXR
Portion removed by water
RTF feedback from last meeting
• Added heat from transfer pump assumed to
be trivial; effect not included in calculation
• Specify that measurements are taken close to
HX to avoid varying system configurations
• COP sensitivity analysis performed
– COP assumptions reasonably accurate across wide
range of expected suction/discharge temps
• Develop COP lookup tables for other common
refrigerants
Protocol changes since November
• Cleaned up verbiage to clarify definitions,
delivery verification and data collection
characteristics
• Removed New Construction from eligible projects
due to missing standard practice baseline
• Added language directing practitioner to measure
water temperatures as close as possible to the
heat exchanger
• Made all refrigerants eligible for the protocol,
with all refrigerants other than R-22 and R-507
assumed to have the same COP as R-404a
Protocol changes since November
• Added supporting documentation to capture
“non-protocol specific” analysis
• Biggest change is restructuring of simplest
reliable method in protocol
– Previously had temp probe measurement as
primary collection method
– Guidelines require alternate methods to be of
sufficient or better reliability
RTF Proposed Motion:
“I _________ move that the RTF approve the Dairy
Heat Exchanger Standard Protocol and assign it to a
“Small Saver” category with “Active” status and a
sunset date of February 20, 2017.”
COP Sensitivity Analysis
• COP dependent on refrigerant, suction & discharge pressures
• Calculator COP assumptions:
•
•
•
Suction temp = 20 °F below storage temp
Typical discharge pressure = 200 psig
Pressure cut-in/cut-out setpoints unchanged if change refrigerant
•
•
i.e. 200 psig discharge pressure remains typical for all 3 refrigerants
Refrigerant is known (R-22, R-404, R-507)
• Table compares energy savings with fluctuating COP (best practice) vs. simplest
reliable method.
• Conclusion  COP assumptions are reasonably accurate across a wide range of
suction/discharge pressures
Suction Temperature
R-22
12
13
14
15
16
17
18
19
20
21
22
23
24
Discharge Pressure (psig)
160
164
22.0%
20.1%
21.9%
20.0%
21.7%
19.8%
21.6%
19.7%
21.5%
19.6%
21.5%
19.5%
21.4%
19.4%
21.4%
19.4%
21.4%
19.4%
21.4%
19.4%
21.5%
19.4%
21.5%
19.4%
21.6%
19.5%
168
18.2%
18.0%
17.8%
17.7%
17.5%
17.4%
17.4%
17.3%
17.3%
17.3%
17.3%
17.3%
17.3%
172
16.3%
16.0%
15.8%
15.7%
15.5%
15.4%
15.3%
15.2%
15.1%
15.1%
15.1%
15.1%
15.1%
176
14.3%
14.0%
13.8%
13.6%
13.4%
13.3%
13.2%
13.1%
13.0%
12.9%
12.9%
12.9%
12.9%
180
12.3%
12.0%
11.8%
11.5%
11.3%
11.2%
11.0%
10.9%
10.8%
10.7%
10.7%
10.7%
10.6%
184
10.3%
10.0%
9.7%
9.5%
9.2%
9.0%
8.9%
8.7%
8.6%
8.5%
8.4%
8.4%
8.4%
188
8.2%
7.9%
7.6%
7.3%
7.1%
6.9%
6.7%
6.5%
6.4%
6.3%
6.2%
6.1%
6.0%
192
6.2%
5.8%
5.5%
5.2%
4.9%
4.7%
4.5%
4.3%
4.1%
4.0%
3.9%
3.8%
3.7%
196
4.1%
3.7%
3.4%
3.0%
2.8%
2.5%
2.3%
2.0%
1.9%
1.7%
1.5%
1.4%
1.3%
200
2.0%
1.6%
1.2%
0.9%
0.6%
0.3%
0.0%
-0.2%
-0.4%
-0.6%
-0.8%
-0.9%
-1.1%
204
-0.1%
-0.5%
-0.9%
-1.3%
-1.7%
-2.0%
-2.3%
-2.5%
-2.8%
-3.0%
-3.2%
-3.3%
-3.5%
208
-2.2%
-2.7%
-3.1%
-3.5%
-3.9%
-4.2%
-4.5%
-4.8%
-5.1%
-5.3%
-5.5%
-5.7%
-5.9%
212
-4.3%
-4.8%
-5.3%
-5.7%
-6.1%
-6.5%
-6.8%
-7.1%
-7.4%
-7.7%
-7.9%
-8.1%
-8.3%
216
-6.4%
-7.0%
-7.5%
-7.9%
-8.3%
-8.7%
-9.1%
-9.4%
-9.8%
-10.0%
-10.3%
-10.6%
-10.8%
220
-8.6%
-9.1%
-9.6%
-10.1%
-10.6%
-11.0%
-11.4%
-11.8%
-12.1%
-12.4%
-12.7%
-13.0%
-13.2%
224
-10.7%
-11.3%
-11.8%
-12.3%
-12.8%
-13.3%
-13.7%
-14.1%
-14.4%
-14.8%
-15.1%
-15.4%
-15.7%
228
-12.8%
-13.4%
-14.0%
-14.5%
-15.0%
-15.5%
-16.0%
-16.4%
-16.8%
-17.1%
-17.5%
-17.8%
-18.1%
232
-14.9%
-15.6%
-16.2%
-16.7%
-17.3%
-17.8%
-18.2%
-18.7%
-19.1%
-19.5%
-19.9%
-20.2%
-20.5%
236
-17.0%
-17.7%
-18.3%
-18.9%
-19.5%
-20.0%
-20.5%
-21.0%
-21.4%
-21.8%
-22.2%
-22.6%
-22.9%
240
-19.1%
-19.8%
-20.5%
-21.1%
-21.7%
-22.2%
-22.8%
-23.3%
-23.7%
-24.2%
-24.6%
-25.0%
-25.4%