Presentation is loading. Please wait.

Presentation is loading. Please wait.

Heating & Cooling (HVAC) 3 Page 39. Sustainable HVAC Operating motors, fans and pumps efficiently Sustainable HVAC technologies Building system controls.

Similar presentations


Presentation on theme: "Heating & Cooling (HVAC) 3 Page 39. Sustainable HVAC Operating motors, fans and pumps efficiently Sustainable HVAC technologies Building system controls."— Presentation transcript:

1 Heating & Cooling (HVAC) 3 Page 39

2 Sustainable HVAC Operating motors, fans and pumps efficiently Sustainable HVAC technologies Building system controls Motors Pages 39-40

3 Motors Inefficiency can result from: Dirty breakers Bad connections and terminations Voltage drop of more than a tenth of a volt indicates connection needs repair. Motors drive fans and pumps in HVAC systems. Bad motor connection: defective crimp Motors Pages 39-40

4 Motors Page 40 Premium® Energy Efficiency Motors National Electrical Manufacturers Association (NEMA) Premium® Energy Efficient Motors program establishes standards for highly efficient motors.

5 Using Variable Frequency Drives for Greater Control Page 40 Replacement of Motors and Drives “Right-Size” Motors! (see MotorMaster guidelines) Undersized motors function poorly Oversized motors waste energy and money Use variable frequency drives (VFDs), or variable speed drives (VSDs), to match speeds to loads

6 Variable Frequency Drive (VFD) VFDs allow for greater control by adjusting the speed of the motor to match the load. Using Variable Frequency Drives for Greater Control Page 40 Circuit Diagram of VFD

7 Using Variable Frequency Drives for Greater Control Page 41 EXAMPLE: Use VFD to Control Fan Speed Adjusting fan speed with a VFD instead of throttling the output uses much less power.

8 Using Variable Frequency Drives for Greater Control Page 41 Wiring a VFD Program can reset when powered off – controller programming may be lost! Always use VFD on/off connections Don’t put an external switch on a VFD unless the instructions explicitly say you can. Variable Frequency Drive Control

9 Fans Pages Oversized fans waste energy Use VFD instead of fan dampers for more energy efficient control Axial fan (more efficient)Centrifugal fan Fans: Axial vs. Centrifugal

10 Pumps Pages Pumps: Centrifugal vs. Positive Displacement Centrifugal Pump Positive Displacement Pump Domestic Water Supply Hydronic Heat Circulation Pumps Domestic Hot Water Circulation Pump Oil Burner Pumps and Oil Circulation Pumps

11 Component Replacement Plan Page 43 Ensure right sized equipment is ready when a component falls apart Store spare parts Have the piping and instrumentation diagrams available Discuss plan with building manager, plumber or HVAC company Replacement Parts List Component Replacement Plan

12 Roof mounted air-source heat pump Moves heat from a heat source to a heat sink (air conditioner) Heat Pumps Pages Heat Pumps

13 Heat Pump / Air Conditioner Cycle Heat Pumps Pages 44-45

14 Horizontal closed loop GSHP Heat Pumps Pages Air-source Water-source Ground-source (GSHP) Types of Heat Pumps

15 HVAC Systems Page 46 HVAC systems are among the largest users of energy in buildings Buildings often outlive their HVAC systems Retrofitting heating and cooling systems can offer great opportunities for energy savings (and jobs) Upgrading HVAC Systems

16 Types of HVAC Systems Page 46 Water carries heat more effectively than air In most green HVAC systems, air is only used for ventilation; all heating and cooling is carried in circulating water Air-and-water systems are more energy efficient than air-only systems Often air-only systems are controlled by dampers - it’s more efficient to use a VFD Selection of HVAC Systems

17 Electric Baseboard Heating Electrical Work in Upgrading HVAC Systems Page 48 Electric resistance heating is cheap to install but… Expensive to operate Inefficient because electricity is generated from fuel at 30-33% efficiency Upgrading HVAC Systems

18 Electrical Work in Upgrading HVAC Systems Page 48 Electrical Work in HVAC Retrofits Permanent labels on wiring to simplify troubleshooting in the future Do not strain wire insulation Opportunity to correct mistakes from original construction

19 Building Control Systems Pages Building Control Systems Building control systems monitor and control the MEP systems in a building. The most common are building management systems (BMS). Control systemsTemperature sensors

20 Types of Building Management and Information Systems Pages Building Management System (BMS) A BMS reduces energy use by: Scheduling equipment and operations to meet demand Controlling temperature, pressure, and humidity in the building, taking weather conditions into account Controlling fans and pumps to optimize HVAC Providing data for analysis

21 CASE STUDY: 31 Tannery Project, Branchburg, NJ First Net-Zero Building in U.S. 31 Tannery Project Page 50 Building control data, automation, and control of energy systems are key to minimal fuel and electrical use in this net- zero energy building.

22 4 Renewable and Distributed Energy Page 51

23 Central vs. Distributed Energy Generation: Central Generation: Power is generated at one central location and transmitted long distances across a grid to consumers Distributed Generation: Occurs close to a load: Lower transmission losses Lower stress on grid by reducing peak load Basic Background: Energy Generation Pages Where is the Energy Generated?

24 What is the Energy Source? Nonrenewable vs. Renewable Energy Generation: Renewable sources will not be depleted over time. Very little CO 2 emissions Decreased pollution Reduced reliance on fossil fuels Site energy almost equal to source energy Examples: Solar thermal Wind farms Basic Background: Energy Generation Page 52

25 POP QUIZ: GENERATION: Central or Distributed? ENERGY SOURCE: Renewable or Nonrenewable? Basic Background: Energy Generation Page 52 Imperial Valley Solar Project, CA Rooftop solar PV array

26 POP QUIZ: Central Generation /Renewable Energy GENERATION: Central or Distributed? ENERGY SOURCE: Renewable or Nonrenewable? Basic Background: Energy Generation Page 52 Imperial Valley Solar Project, CA Rooftop solar PV array Distributed Generation /Renewable Energy

27 POP QUIZ: GENERATION: Central or Distributed? ENERGY SOURCE: Renewable or Nonrenewable? Basic Background: Energy Generation Page 52 Coal-fired power plant, GA70 kW microturbine - Cogen

28 POP QUIZ: GENERATION: Central or Distributed? ENERGY SOURCE: Renewable or Nonrenewable? Central Generation / Nonrenewable energy Distributed Generation / Nonrenewable energy Basic Background: Energy Generation Page 52 Coal-fired power plant, GA70 kW microturbine - Cogen

29 Radial and Networked Systems Radial: Power lines branch out Networked: Power lines interconnected Utility Grid Pages 52-53

30 Secure Disconnects A secure disconnect on a distributed generator protects utility workers attempting to restore power. Utility Grid Page 53

31 Net metering Find incentives at the Database of State Incentives for Renewables and Efficiency (dsireusa.org) Utility Grid Page 53 Selling Energy Back to the Grid

32 A typical power plant can lose 67% of its fuel input to waste heat. Cogeneration: Combined Heat and Power Page 54 Standard Energy Generation Wastes Heat

33 Cogeneration: Combined Heat and Power Page 54 Cogeneration: Combined Heat & Power (CHP) Cogen captures and uses “waste” heat. A CHP system uses waste heat usually lost to the environment.

34 Must be sized to load. Don't make energy you can't use! A cogen system needs to run at full capacity all the time to be cost-effective. Design it to meet the electric or thermal base load, whichever is SMALLER. Cogeneration: Combined Heat and Power Pages Sizing a Cogen Unit

35 Average Electrical Demand Domestic Hot Water Consumption Sizing a Cogen Unit Pages Sizing a Cogen Unit Actual power base load is 100 kW Existing thermal loads of the building would require only 16 kW unit Adding hot water storage tanks increases thermal load to 27 kW

36 Possible deal breakers if the following requirements are not met: The location must allow adequate clearance for maintenance. The location must also be close to gas, electricity, and waste heat connections. There must be adequate natural gas capacity or a relatively inexpensive way to provide a new gas line. There must be an allowance for combustion products to discharge. See cost considerations on page 55 of the manual. Sizing a Cogen Unit Pages Economics of Cogen - Retrofit

37 Sizing a Cogen Unit Page 56 Can Cogen be Used as a Backup Generator? Induction – NO! Majority of cogen systems Requires voltage from utility to operate If utility down, cogen is down Synchronous – YES! Does not require voltage from utility Many code restrictions

38 Types of Cogeneration Systems Reciprocating Engine: Most common type of cogen Microturbine: Smaller-scale, fewer moving parts but new to market Large-Scale Cogen: Gas turbines (industrial applications only) Engine-Driven Chillers: Reciprocating engine drives standard cooling compressor Trigeneration: Produces electricity, heat in winter and cooling in summer Cogeneration: Combined Heat and Power Pages 57-58

39 Fuel Cells Page 59 Fuel Cells

40 PV systems convert sunlight into electricity via photovoltaic effect PV effect occurs in semiconductor materials like silicon Practical efficiencies between 8% and 20% Solar Photovoltaic Power Page 60 Solar Photovoltaic Power

41 Connections of PV Cells Electrical Generation and PV Systems Page 61 Parallel High current Low voltage Series Low current High voltage

42 I-V Curves for a PV module at different levels of insolation. Power output is zero when V = 0 or I = 0, maximum on the shoulder of the curve. Solar Photovoltaic Power Pages PV Performance

43 Stand-alone PV system with battery storage. PV Performance Page 62 Storing Solar Power

44 PV wiring with AC conversion for grid connection. PV Performance Page 62 Storing Solar Power

45 DC to AC Conversion: PV cells provide DC power Building systems are AC Inverter converts DC power to AC power Solar Photovoltaic Power Pages Additional Components of PV Systems

46 DC to AC PV system string inverter Outdoor connection requires: Protection from corrosion Sufficient slack to allow for thermal expansion and contraction Allowance for the removal and replacement of modules Inverters Additional Components of PV Systems Pages 62-63

47 Roof mounted PV system Maximize on-building systems: Orientation: Perpendicular to the sun, facing south at an angle to the horizontal, slightly shallower than the angle of latitude Shading: Avoid shading! Reduces output of whole cell string Placement: Avoid overshadowing Types of PV Systems Page 63 Building-Mounted Systems

48 Types of PV Systems Pages Large-Scale Systems

49 Amorphous thin film technologies have lower efficiency but may provide lower overall cost HIT PV cell development may also lead to lower PV cost Solar Photovoltaic Power Page 64 New PV Technologies are Reducing Costs

50 New PV Technology Page 64 Simple Payback Analysis Analysis CategoriesCost PV panel cost with installation$300,000 Federal tax credit (one-time)- $90,000 State energy program incentive- $95,000 Net invested capital= $115,000 Anticipated operated savings/year+ $15,000 Payback period$115,000 / $15,000 = 8 YEARS 50 kW rooftop solar PV system

51 National certification: Solar Photovoltaic Power Page 65 PV Installer Certification Underwriters Laboratory Regional Certification Manufacturer Certification

52 Wind farm near Tehachapi, CA Off-shore wind farms Mountain ranges Great Plains Wind Power Pages Wind Power: Utility-Scale Effectiveness depends on wind speed and consistency.

53 Brooklyn Navy Yard, Brooklyn, NY Concerns: Not cost-effective Less consistent Stresses to existing building Machine failure in densely populated environments Wind Power Pages Wind Power: Building-Mounted Systems

54 East River Turbine, RITE Project, New York, NY Tidal Turbines Harvest energy in the tides. Tidal Turbines Page 68

55 Electric vehicle charging system, Syracuse, NY Electric Vehicle Charging Systems Electric vehicles are cleaner to run than internal combustion vehicles. As they become more common, electricians will find more opportunities in EVSE (Electric Vehicle Service Equipment). Electric Vehicle Charging Systems Pages 68-69

56 CLASSROOM EXERCISE #2 BASIC PV DESIGN A homeowner is considering installing PV panels on an existing roof. See details on page What size array can be installed? How many panels can be included and what is the total area? 2.If the peak power available at this roof angle is 93 W/sf, what is the peak output of the array? 3.What is the total installation cost? The cost after incentives? Pages 70-71

57 CLASSROOM EXERCISE #2 BASIC PV DESIGN 4.Using the map on the page 71, how much energy do the PV panels produce in a year? 5.How much is saved in energy costs per year? 6.How long is the payback period? (See Figure 4.20 in manual for Simple Payback Analysis) 7.Give two or three reasons for converting electricity from the PV panels to AC, rather than leaving it as DC and storing the energy in batteries for back-up during power outages. (Compare to using a fuel powered generator during the outage.) Pages 70-71


Download ppt "Heating & Cooling (HVAC) 3 Page 39. Sustainable HVAC Operating motors, fans and pumps efficiently Sustainable HVAC technologies Building system controls."

Similar presentations


Ads by Google