Presentation on theme: "Texas Utility Innovations"— Presentation transcript:
1 Texas Utility Innovations A discussion onHVAC’s Variable Refrigerant Flow (VRF) Technology & IEER Efficiency MetricsSteve Jones - Southwest Business Unit Commercial Manager – Mitsubishi ElectricNick Conklin LEED AP, PE, CEM – Application Engineering Manager – Mitsubishi ElectricGood morning (afternoon). We’re going to spend the next 15 minutes talking about innovations in HVAC technology – specifically the HVAC industry’s newest technology called Variable Refrigerant Flow Technology (or VRF). We also want to discuss how the efficiency metric, Integrated Energy Efficiency Ratio (IEER), is being used to accurately predict energy savings and assist utilities in developing programs to incentivize growth for this energy saving technology.
2 EEIP Guidelines to Address Why is Ductless Heat Pump (DHP) / Variable Refrigerant Flow (VRF) a Commercially-ready new technology or existing underutilized technology?Overview of the DHP/VRF for EECM(s) – A description of the technology, target market with market potential, and estimated installed/implementation costsWhy Verifiable peak demand savings (kW) and/or energy savings (kWh) is achievable?Energy Modeling using IEER metricsEnergy Saving Case Studies – Sacramento Drill TowerMeasurement and Verification (M&V) – SMUD and PG&E utility savingsApplicability in Texas Utility MarketSOPMTPWhat are Texas PUC needs for Energy Efficiency Conservation Measures and/or the Energy Efficiency Goal ? How do we get VRF and IEER metrics in place for utility programs?Here are the EEIP Guidelines that we want to address today.One of our main questions for PUCT is - what PUCT is hoping to learn from this session and how Mitsubishi Electric can support this process with future more in-depth meetings?What are the next steps in this process?
3 US HVAC Industry Overview Commercial/Industrial HVAC Choices:Package SystemsSplit SystemsVRF SystemsLight Commercial/Residential HVAC Types:PTACsUnitaryWindow unitsWall-mounted unitsRadiantDuctless (DHP)All buildings have some type of heating, ventilation and air conditioning. For large commercial and industrial applications, HVAC options fall under one of these three categories:Package Systems – the HVAC system is contained in one unit. This type of HVAC system can include traditional boilers, chillers, water-source heat pumps, multi-zone rooftop units – basically any system that is based on water or direct expansion (DX). Typically, conditioned air is ducted from the system to the indoor space through ducts.Split Systems – the system has two parts, usually an indoor and outdoor unit. Again, the components of this system can include boilers, chillers, water source heat pumps, etc. Typically, these systems move refrigerant instead of air.VRF Systems – a flexible version of both of the more traditional options, with the key difference being that VRF reacts to changes in cooling and heating requirements by varying the flow of refrigerant as opposed to moving chilled or heated air through ductwork. This is the newest and most exciting HVAC technology choice.For smaller residential and light commercial buildings, common HVAC solutions include PTACs, unitary (traditional central air conditioning), window units, wall-mounted units, radiant and ductless.*Room AC not included in analysisSource: AHRI and BRSI, September 2012
4 US Vertical Market Opportunities 31% HVAC Unit GrowthVertical MarketYearMarket Size (Units)Education2007190,0002012300,000Government/ Military84,00097,000Health Care79,000145,000Lodging40,00054,000Multi-Family270,000317,000Office Building74,000104,000The tide is turning, however. The market is moving from what some would describe as “horse and buggy” technology to state-of-the-art solutions. This has already happened in other parts of the world where VRF technology is the preferred way to control interior comfort. There continues to be a strong need in a number of vertical markets for the solutions that ductless and VRF systems provide. These markets – education, government/military, healthcare, lodging, multifamily and offices – represent just a portion of the opportunity. Other key vertical markets include churches and public buildings such as museums, civic centers and performing arts facilities.Source: FMI 2008 U.S. Market Construction Overview
5 Ductless Heat Pumps for Single Zones (30+ Years HVAC Market Success) Highly Efficient26 SEER10.6 HSPFNo ductwork = No duct lossesIndividual Room ControlExtremely Quiet19 – 38 dBCold Climate Capable100% capacity at 5 F.82% capacity at -13 F.This is the most basic type of DHP – Ductless Heat Pump system, often referred to as Ductless Mini-Splits. It has one outdoor unit to one indoor unit. It cools and heats the space or zone and has it’s own control mechanism. With most manufacturers – the outdoor unit has an inverter compressor (variable speed device) to control how much refrigerant is sent to the indoor unit. The indoor unit senses the required cooling or heating capacity (refrigerant flow from the outdoor unit) and increases or decreases fan speed with an ECM (electronically commutated motor) to condition the indoor zone. In many applications these are used to better condition a room addition or “hot / cold zone” in the residence/building. They are also used to help “displace” the existing central AC/Heat in the main part of the house/building to lower energy use.
6 VRF for Commercial Buildings Up to 50 indoor units per outdoor72,000 – 360,000 BTUHSimultaneous heating and coolingEnergy reclaimIEER up to 23.9COP up to 4.87VRF Systems are the enhanced commercial versions of Ductless Mini-Split systems. VRF systems permit more indoor units to be connected to the outdoor unit and offer additional features such as Simultaneous Heating and Cooling different zones and Heat Recovery.
7 What is VRF Technology?VRF technology is a HVAC technology solution to efficiently condition buildings, zoned for comfort. This is accomplished through the use of an inverter driven (variable speed) compressor. The system is made up of a central variable capacity outdoor unit connected to multiple variable capacity indoor units. A typical installation considers a building’s diversity, driven by a variety of circumstances, including time of day, exposure to sun and other elements, and the occupants. Because the compressor can vary its speed and capacity, and the indoor units can very their capacity; the system delivers the capacity to precisely meet the load in each zone.7
8 INVERTER-driven Compressor SETPOINTVRFVRFCONVENTIONALRoom TemperatureEnables capacity operation as low as 4%Sizing flexibility with variable capacityEnables long runtimesReduces compressor cyclingImproves temperature controlVRFThe chart shows the advantage of inverter-driven compressors common in most VRF systems. Uniform temperatures are maintained as a result of finely tuned control of the compressor speed. Traditional HVAC systems, maintain temperatures by turning the compressor off and on, demanding the maximum energy input each time the system starts.Time8
9 High Starting Current Traditional HVAC System without Inverter Technology The installation of variable speed air conditioning systems, motors, and drives is already an EECM in the state of Texas. VRF Inverter Compressor Technology is the same type of technology as a Variable Frequency Drive used for electric AC motors driving fans and pumps.This is an important aspect for Demand Response Tools – as the VRF Control System can accept a signal from the Building Management System once the Demand Response trigger is initiated. The VRF controls then slow down the inverter compressor reducing energy demand from the VRF system, but allowing the VRF system to continue to provide reduced amounts of AC/Heat to the building occupants – versus an on/off situation – and occupant discomfort.
10 Diversity Solar Load Occupant Load Building Use 10 Utilizing a building’s diversity is a key advantage of VRF systems. These systems can distribute cooling capacity to keep up with changing solar loads, or as people travel throughout a building. They can cool and heat simultaneously, to provide heat at the perimeter and cool the interior of a building without any waste heat.10
11 VRF Heat Recovery Technology A simultaneous cooling and heating (heat recovery) system includes an outdoor unit, a BC controller, indoor units and a control system. Heat recovery systems take further advantage of diversity by taking the energy used to cool one part of the building and using it to heat another part of the building. Because of this feature, heat recovery systems are offered with a connected capacity of up to 150 percent. Typically, these systems are available up to 24 tons.Simultaneous cooling and heating
12 VRF Integrated Controls Easy to install and operate2-wire DDC (Direct Control) system16ga stranded and shielded, non-polarDaisy-chain connectionCustomizable control scheme with web accessIndividual room controlsColor touch screen centralized controlIntegration into building management system via BACnet® and Lonworks®Third-party equipment controlTenant billing capabilityVRF systems utilize an integrated controls network that links the entire system. The integrated controls network allows all parts of the VRF system to communicate, constantly maximizing efficiency and dialing in the capacity of the system. The controls network can be tied into a standard building management system (BMS). The controls network also offers Tenant Billing which when combined with watt meters at the outdoor gives the building owner the ability to bill each tenant individually.
13 VRF Energy-Efficiency and Environmental Impact 13
14 Demand Response Tool VRF Integrated Control Systems can allow: Load shedding by automatically reducing compressor frequency/hertz (speed).On/Off Sequencing between zones to minimize temperature discomfortTurn off indoor units in several zones and allow temperature/humidity driftSequential starting of outdoor units to minimize demand power spikesThe Integrated Controls that come standard with VRF Systems allow a Building Management System to control the VRF System once a Demand Response Signal is sent. There are a variety of options that can be deployed to help minimize energy consumption without completely shutting the HVAC system off. The VRF Controls allow customized energy shedding options that the building owner determines are best suited for their needs.
15 Utilizing VRF with LEED Energy and Atmosphere: VRF Can achieve up to 21 pointsEnvironmental Quality: VRF can achieve up to seven pointsLEED NC 3.0Certified: pointsSilver: pointsGold: pointsPlatinum: 80 + pointsVRF system can contribute a great deal to meeting LEED requirements providing up to 21 points in Energy and Atmosphere and seven point in Indoor Environmental Quality.
16 Energy and Atmosphere Credits Eac1 – Optimize Energy UsageTotal energy usage of buildingVerified by modeling versus base buildingEAc5 – Measurement and VerificationVerify actual building operationMonitor equipment operation through integrated softwareIn the Energy and Atmosphere section of LEED, VRF systems help in optimizing energy performance, providing Maintenance Tool software for accountability and optimizing building energy consumption over time.
17 VRF Systems and Energy Modeling Energy usage and cost for VRF systems can be modeled using EnergyProEnergyPro uses DOE2.1e to model and compare VRF to other HVAC systemEnergyPro is approved use with LEED EAc1Through a partnership with EnergySoft, selected VRF manufacturers helped integrate VRF functions into an existing software tool – called EnergyPro – which can be used to model VRF systems. EnergyPro energy modeling results are acceptable for use in LEED documentation (EAc1). EnergyPro is available to designers and engineers at a discounted price through many VRF manufacturers. To date, EnergyPro is the only software with the capability to model VRF systems.VRF system can contribute a great deal to meeting LEED requirements providing up to 21 points in Energy and Atmosphere and seven point in Indoor Environmental Quality.In the Energy and Atmosphere section of LEED, VRF systems help in optimizing energy performance, providing Maintenance Tool software for accountability and optimizing building energy consumption over time.17
18 EAC1 - Energy Cost Savings The chart above shows the total building energy cost results of an energy model comparison done on a single story school. The building was set up to be code compliant. The only factor that was changed was the HVAC system. The VRF system was compared to a 4-pipe fan coil unit system, a water source heat pump system, and a packaged VAV with hot water reheat. In many cases installing a VRF system met or exceeded the 10 percent energy cost savings required by prerequisite and also meets or exceeds the 12 percent required to achieve points under EAC1.VRF Total Energy Cost Savings
19 Overview of System Standards AHRI 1230Covers multi-split air conditioners and multi-split heat pumps with distributed refrigerant technologyASHRAE 90.1Minimum requirements for energy efficient building designHigher standard for VRF system Integration Energy Efficiency Ratio (IEER) in ASHRAE standard 90.1 (July 2012)DOEDOE to reference AHRI 1230 Standard and ASHRAE 90.1 minimum efficiency standards in Code of Federal Regulations part 10, section 431
20 How IEER Weighting Factors Developed To Develop the four weighting factors for the IEER equation as well as the ambient temperature schedule, a comprehensive model was developed :Weather Data Model For Cities From 15 US Climate ZonesPercentage of Time In The Four Load Bins 100%, 75%, 50%, 25%Average Ambient For Each Load Bin3 Buildings types – Office (40%), Retail (30%), School (30%)Each building type with its load profile vs. ambient scheduleSales Volumes Percentage By Each Climate Zones
21 Sacramento Drill Tower VRF Case StudyOwned by the City of Sacramento, CAConcrete Building with Upper 1/3 being a water tankApproximately 2/3 of the first floor area are offices and a training room, arranged like a donutOriginal HVAC was 4 pipe ducted fan coils, with a natural draft gas boiler and 30 ton air cooled chiller.Equipment replaced with (2) 16 ton VRF heat recovery type systems in 2008, with 4 ducted fan coils each, and an ERV
22 Sacramento Drill Tower – VRF Case Study Significant reduction in Energy Consumption (kWh)
25 Metered Data From Drill Tower Total Gas CostTotal Electrical CostTotal CostBefore CITY MULTI - VRF (2007)$5,987.44$19,456.78$25,444.22After CITY MULTI - VRF (2009)$455.03$18,607.36$19,062.39Percent Savings92.4%4.4%25.1%*Based on Data Provided from SMUD and PGE Building is located in Sacramento
26 Re-Cap: Benefits of VRF Systems Space UtilizationInstallation flexibility to meet building space requirementsMinimal impact to existing building architecture and structureOccupant ComfortIndividual comfort controlIndoor unit flexibility to meet the needs of any spaceMeets occupant ventilation air requirementsQuiet operationEnergy SavingsInverter driven compressorNo waste heatMeets requirements for LEED points
27 Texas Utility SOP / MTP Programs In closing, I would like to ask the board to please support the development of programs in the state that appropriately incentivize VRF systems. By adding a VRF category to the Texas Energy Efficiency Goal utilizing the appropriate energy efficiency metric IEER, utilities will accurately capture the associated energy savings and properly incentivize the technology.27
29 Successful Utility Programs - West Prescriptive VRF Incentive$1,500/ton upstream rebate on up to 80 tons for commercial applicationsLet’s take a look at a couple successful VRF incentive programs in the US. SCE put a VRF incentive program in place in 2010 and PG&E followed along with a program in This incentive is an upstream rebate to the VRF distributors, and provided a range from $630 to $1,530 a ton for up to 80 tons for commercial applications. Quite a lucrative rebate indeed.