Clima-Flex VRW

(Variable Refrigerant Water) y su eficiencia energé7ca

Equipment Efficiency vs. AHRI unit efficiency • AHRI – At least 3 manufactures have to agree to join and pay AHRI to have a subsec@on created for their equipment.

– With the required compe@@on maintained the manufactures with considera@on for lab capability agree on a method to compare their equipment against each other.

– They also create the standard for new members to test against.

• Tradi@onal – ARI: Cooling was the same for each sec@on – hence EER. It was also known that water-­‐cooled was more efficient than air-­‐cooled equipment but the purpose of the test was comparison – not codes or energy bills.

Evolu@on and the divergent path • SEER – Residen@al furnaces with DX cooling added found that the EER number made them look bad, so all furnace manufactures got together and created a test that was “Seasonally” adjusted for one locality and all agreed to compare to that set of condi@ons.

– Just like the auto MPG ra@ng. It varies for the type of vehicle but it is not meant to be the way you drive – just the same for all manufacturers.

• The beginning of part load or adjusted performance ra@ngs – Manufacturers looked at barriers to entry in seSng the test criteria.

– Manufactures colluded to make equipment performance look beTer – SoUware programs try to applied numbers in modeling

Benchmarking and performance monitoring • • •

It starts with monitoring and repor@ng It will grow to be more accurate But it will never be as easy as a simple number – Too many variables in the building – Too many variable outside the building

• •

But we do know the basic truths Star@ng with the headquarters for the ASHRAE Headquarters Building – Designed for comparison – And publicly monitored

System Comparison – look at real results ASHRAE Headquarters Building - Atlanta, GA –

First floor

–

Second floor

• •

VRF Offices and classrooms

• •

Geothermal heat pump Offices and meeting rooms

System Efficiencies as monitored

ASHRAE Headquarters Building

System Efficiencies vs. units tested for certification

ASHRAE Headquarters Building

Cooling System Efficiencies published vs. actual Geothermal Heat Pump Vs. VRF 25.0

Cooling IEER.

20.0

Measure d

15.0

10.0

5.0

48% Difference

8% Difference

0.0

VRF Cooling IEER

GSHP Cooling IEER

ASHRAE Headquarters Building

Heating System Efficiencies published vs. actual Geothermal Heat Pump Vs. VRF 06

Heating COP

05 04

Measured Published

03 02 01

53% Difference

24%$Difference$

00

VRF Heating COP (Ducted Unit)

GSHP Heating COP

ASHRAE Headquarters Building

System Efficiencies – an actual reading

VRF Power Demand Ambient = 36F

Geo HP Power Demand

ASHRAE Headquarters Building

Generation Energy 1st Law of Thermodynamics • 1st Law of Thermodynamics • Stuff in – stuff out = stuff left • (ΔQin + ΔWin) – (ΔQout + ΔWout) = ΔE • Where ΔE = Change in Energy • ΔQ = Change in heat • ΔW = Change in Work • For a closed cycle (power or refrigeration) • Stuff left = 0 or Stuff in = Stuff out • ΔE = 0 or ΔQin + ΔWin = ΔQ0ut + ΔWout

Refrigeration Cycle

ΔQo ut

Flow Diagram d = hot liquid

Expansi on Valve

For Process:

ΔQout = ΔQin (from space) + ΔWin

c = hot vapor Conden ser

Evapora tor a = cold liquid

Compre ssor Δ Win b = cold vapor

ΔQin (from space)

Carnot Refrigeration Cycle TReject

d

c

bc = Work added by compressor

ed

T (Temperature)

TAdde d

Work Supplied a

cd = Heat rejected by condenser

b

Refrigeration (Heat Added From Space) S (Entropy)

ab = Heat added from evaporator (space)

da = Work produced by expansion (throttling) valve

1st Law of Thermodynamics •

1st Law of Thermodynamics as Refrigeration Cycle – Efficiency = COP (Coefficient of Performance) = Heat rejected (from space)/Work in = ΔQin from space/ΔWin from compressor (dimensionless) = TA/(TR – TA) – Where • TR = Temperature of heat sink for rejected heat • Lower the heat sink temperature the higher the efficiency

1st Law of Thermodynamics • 1st Law of Thermodynamics as Refrigeration Cycle – Efficiency of Heat Sinks • Air Cooled – Dry bulb air temperature (95F to 110F) – Least efficient

• Water Cooled – Wet bulb air temperature (65F to 80F) – More efficient

• Earth Cooled/Geothermal – Ground temperature (50F to 75F) – Most efficient

1st Law of Thermodynamics • Increase in Efficiency for Variable Speed ~20%

Equipment Efficiencies •

AHRI Heat Sink Rating Conditions for Part Load

Equipment

AHRI Rating Standard Designation

Ambient Testing Conditions (F) 100% 75% 50% 25% Part Load Part Load Part Load Part Load

Chillers, Air Cooled Chillers, Water Cooled Condensing Units, Air Source Heat Pump, Air Source Heat Pump Geothermal (Closed) Water Loop

550/590 550/590 365 340/360 Same as 550/590 Heat Pump,Geothermal (Closed) Ground Loop 13256 Heat Pump, Geothermal (Open) Ground Water 13256 Variable Refrigerant Flow, Air Cooled 1230 Variable Refrigerant Flow, Water Cooled 1230

IPLV IPLV IPLV IEER IEER

95 85 95 95 85

80 75 81.5 81.5 75

65 65 68 68 65

55 65 65 65 65

IEER IEER IEER IEER

77 59 95 85

77 59 81.5 73.5

77 59 68 62

77 59 65 55

System Efficiencies part load inside plus outside? •  Part Load Chiller Efficiencies at AHRI Rating Conditions

Equipment Efficiencies at AHRI test Equipment does not operate like this!

Hydronic systems are controlled vs. Outdoor Ambient  AHRI Rating Weighting Conditions for Part Load Equipment

AHRI Rating Standard Designation

Weighting Factors 100% 75% 50% 25% Part Load Part Load Part Load Part Load

Chillers, Air Cooled Chillers, Water Cooled Condensing Unit, Air Cooled Heat Pump, Air Source Variable Refrigerant Flow, Air Cooled Variable Refrigerant Flow, Water Cooled

550/590 550/590 365 340/360 1230 1230

IPLV IPLV IPLV IEER IEER IEER

0.01 0.01 0.01 0.02 0.02 0.02

0.42 0.42 0.42 0.617 0.617 0.617

0.45 0.45 0.45 0.238 0.238 0.238

0.12 0.12 0.12 0.125 0.125 0.125

Equipment Efficiencies Design has to consider multiple system effects AHRI Energy Source Inclusion for Part Load Equipment

AHRI Rating Standard Designation

Energy Source Inclusion Condenser Evaporator Chilled Refrigerant Condenser Cooling Fan Fan Water Pump Water Pump Tower Pump Fan and Pump

Chillers, Air Cooled Chillers, Water Cooled Condensing Units, Air Cooled Heat Pump, Air Source Heat Pump, Water Source Heat Pump, Geothermal (Closed) Gound Loop Heat Pump, Geothermal (Open) Ground Water Rooftop Units Variable Refrigerant Flow, Air Cooled Variable Refrigerant Flow, Water Cooled

550/590 550/590 365 340/360 13256 13256 13256 340/360 1230 1230

IPLV IPLV IPLV IEER IEER IEER IEER IEER IEER IEER

Yes Yes Yes

Yes Yes

No No No Yes Yes Yes Yes Yes Yes Yes

No No

Minimal Minimal

No

No

No No No

No

Distribution in water - Pumping Energy Hydronic pumps use the lowest system energy Distribution/Pumping Energy Hydronic Air (Low Pressure VVT) Air (Medium Pressure VAV) Refrigerant (VRF)

Percent of Compressor Horsepower

35.0% 30.0% 25.0% 20.0% 15.0% 10.0% 5.0% 0.0% 0

100

200

300

Pipe/Duct Length

400

500

Distribution/Pumping Energy – speed kills Farther, faster, higher pressure all = Horsepower • Maximum Velocities – Hydronic •

Pipe

= 6 fps

Low Pressure Duct (900 fpm) Medium Pressure Duct (VAV) (2500 fpm)

= 15 fps

– Air • •

= 40 fps

– VRF • •

Liquid Pipe (360 fpm) Suction Pipe (4000 fpm)

= 6 fps = 66 fps

Distribution of Comfort = Pumping Energy • •

Load – Sample building of 100’ x 100’ – Load at 25 btuh/sq. ft. = 25 x 100’ x 100’ = 250,000 btuh Hydronic (Pump) Horsepower • Flow rate = 250,000 / 500 / 12F ΔT = 42 gpm • Head for 200 ft of hydronic pipe – Pipe = 200 ft. x 1.3 eq. length x 4 ft/100 ft = 10.4 ft.

• Pump HP = 42 gpm x 10.4 ft / 3960 / .75 pump eff. = .15 HP • Pump HP percentage of compressor HP Compressor HP = 250,000 btuh / 5 COP / 3413 btuh/kwh / .75 kw / hp = 19.5 hp Pump HP percentage of compressor HP = .15 / 19.5 = 0.77%

Distribution in Air/Pumping Energy •

Air (Low Pressure Fan) Horsepower • Flow rate = 250,000 / 1.085 / 25F ΔT = 9,220 cfm • Static for 200 ft. of ductwork – Duct = 200 ft x 1.3 eq. length x .1 in/100 ft = .26 in • Fan HP = 9,220 cfm x .26 in / 6346 / .65 fan eff. = .58 HP • Fan HP percentage of compressor HP Compressor HP = 250,000 btuh / 5 COP / 3413 btuh/ kwh / .75 kw / hp = 19.5 hp Fan HP percentage of compressor HP = .58 / 19.5 = 3.0% 4 times more

Distribution in Air (more or smaller duct) higher Pumping (fan hp) Energy •

Air (Medium Pressure Fan) Horsepower • Flow rate = 250,000 / 1.085 / 25F ΔT = 9,220 cfm • Static for 200 ft. of ductwork – Duct = 200 ft x 1.3 eq. length x .3 in/100 ft = .78 in • Fan HP = 9,220 cfm x .78 in / 6346 / .65 fan eff. = 1.74 HP • Fan HP percentage of compressor HP Compressor HP = 250,000 btuh / 5 COP / 3413 btuh/kwh / .75 kw / hp = 19.5 hp Fan HP percentage of compressor HP = 1.74 / 19.5 = 8.9% 11+ times more

Distribution of refrigerant - Highest Pumping Energy •

VRF (Compressor) Horsepower

– Compressor Pump HP for 200 ft. of refrigerant pipe AHRI 1230 – 2013 Table 4. Refrigerant Line Length Correction Factors Percentage of Compressor Power Piping length beyond minimum, X (ft) 3.3 < X ≤ 20

Piping length beyond minimum, Y (m)

Cooling Capacity Correction, %

1 < Y ≤ 6.1

1%

20 < X ≤ 40

6.1 < Y ≤ 12.2

2%

40 < X ≤ 60

12.2 < Y ≤ 18.3

3%

60 < X ≤ 80

18.3 < Y ≤ 24.4

4%

80 < X ≤ 100

24.4 < Y ≤ 30.5

5%

100 < X ≤ 120

30.5 < Y ≤ 36.6

6%

– Compressor Pump HP percentage of compressor HP = 200 ft x 6%/100 ft = 12% 15+ 7mes more than water

Distribution of Refrigerant Pumping Energy •

AHRI Standard 1230 for rating VRF equipment

– Testing standard requires only 25’ of pipe for test installation

Distribution of refrigerant Pumping Energy NO LIFT

• Manufacturer’s Engineering Data

Distribution of refrigerant per test not building Pumping Energy consumption vs. efficiency

• Manufacturer’s Marketing Data

Equipment vs System Efficiencies a challenge • •

Energy Source Derating for System IEER Derating for actual vs. test – a computer program(er)

Equipment

AHRI Rating Standard Designation

Energy Source Derating for System IEER Condenser Evaporator Chilled Refrigerant Condenser Cooling Fan Fan Water Pump Water Pump Tower Pump Fan and Pump

Chillers, Air Cooled Chillers, Water Cooled Condensing Units, Air Cooled Heat Pump, Air Source Heat Pump, Water Source Heat Pump, Geothermal (Closed) Gound Loop Heat Pump, Geothermal (Open) Ground Water Rooftop Units Variable Refrigerant Flow, Air Cooled Variable Refrigerant Flow, Water Cooled

550/590 550/590 365 340/360 13256 13256 13256 340/360 1230 1230

IPLV IPLV IPLV IEER IEER IEER IEER IEER IEER IEER

3.8% 7.7% 3.5%

2.7% 5.3%

12.0% 12.0%

4.8%

4.7%

4.4% 6.4% 13.0%

4.3%

2.6%

2.5%

Total

6.5% 22.5% 3.5% 0.0% 8.7% 6.4% 13.0% 0.0% 12.0% 17.1%

Equipment Efficiencies at AHRI test standards Equipment does not operate like this!

But DOE, codes and rebates want and answer AHRI Rating Weighting Conditions for Part Load Equipment

AHRI Rating Standard Designation

Weighting Factors 100% 75% 50% 25% Part Load Part Load Part Load Part Load

Chillers, Air Cooled Chillers, Water Cooled Condensing Unit, Air Cooled Heat Pump, Air Source Variable Refrigerant Flow, Air Cooled Variable Refrigerant Flow, Water Cooled

550/590 550/590 365 340/360 1230 1230

IPLV IPLV IPLV IEER IEER IEER

0.01 0.01 0.01 0.02 0.02 0.02

0.42 0.42 0.42 0.617 0.617 0.617

0.45 0.45 0.45 0.238 0.238 0.238

0.12 0.12 0.12 0.125 0.125 0.125

System Efficiencies â&#x20AC;&#x201C; how do we apply

System Efficiencies

System Efficiencies

The Industry of Modeling • Need

– Peak performance or lack of performance at extremes – Part load performance per building opera@on

• Outdoor air is documented but performance at limits not available • Hydronic system limits are designed in to your building – Need part load matrix » Condenser water » Chilled water » Hot water » water source closed loops » GeoExchange loops

What is known…A hydronic system always wins!

• Water-­‐cooled equipment is more efficient than air-­‐cooled

– Manufacturers of both products prove that within their own catalog data – Thermodynamics proves it – Weather data proves that a hydronic system has the advantage

• Hydronic systems use the lowest transport energy • Hydronic systems use the lowest refrigerant per ton (1lb. vs. 3 to 4lbs.)

• Hydronic Systems offer more choices – Compe@@ve advantage, more solu@ons, higher comfort

• Hydronic Systems are sustainable because they integrate the building energy profile and are adaptable to technology within the budget.

Including adap7ng to the next change of refrigerants!

HYDRONICS IS SAFE, SUSTAINABLE, Comfortable When refrigerants change will your system be obsolete?

www.hia-­‐c.org