Centerpoint Energy, Inc (holding Co) · NYSE:CNP
Centerpoint Energy, Inc (holding Co) — Technical Presentation (February 2014)
33 slides from Centerpoint Energy, Inc (holding Co)'s technical presentation, Feb 20, 2014
Slide 1: Condensing Heating Rooftop Units (RTUs)
Condensing Heating Rooftop Units (RTUs) Douglas Kosar Senior Institute Engineer Gas Technology Institute CenterPoint Energy Webinar February 20, 2014
Slide 2: Webinar Presenter
Webinar Presenter >Douglas Kosar Senior Institute Engineer Gas Technology Institute >30+ years experience introducing new technologies to buildings >Last 5 years working to introduce condensing heating RTUs through ─ product R&D w/manufacturers ─ national account/other end user pilots ─ Consortium f
Slide 3: Webinar Learning Objectives
Webinar Learning Objectives >Recognize the diversity in a given commercial building of individual RTU heating runtime/gas use >Apply higher efficiency heating RTUs in the most cost effective commercial building applications >Understand complexities of handling RTU combustion condensate, especially i
Slide 4: Webinar Agenda
Webinar Agenda – 50 minute presentation/10 minute Q&A >Individual RTU heating runtimes on a building >Initial ventilation markets for condensing heating ─ Dedicated Outside Air Systems (DOAS), for example >Condensing DOAS pilot in big-box retail stores ─ Net operating energy and cost savings, w/fan
Slide 5: Setting the Stage for Condensing RTUs
Setting the Stage for Condensing RTUs >High efficiency, condensing heating RTUs are entering the commercial marketplace, BUT … >Lack of non-condensing RTU heating load data on which to base savings & paybacks for condensing ─ Conflicting DOE & ASHRAE building modeling results ─ No RTU by RTU dataset
Slide 6: GTI Baseline RTU Testing
GTI Baseline RTU Testing >1 small office >3 quick service restaurants >3 drug/convenience stores >3 clothing/home goods stores >1 retail “super” store Source: GTI 6
Slide 7: Heating Runtime & Gas Use Diversity
Heating Runtime & Gas Use Diversity >Perimeter RTUs w/longer runtimes while core RTUs w/shorter runtimes (in general, excess core RTU capacity increases w/area of building) >HI heat sees limited use – can benefit from 2 stage fan to reduce fan energy penalty in LO heat Perimeter RTUs (1, 2, 3, & 5)
Slide 8: Usage Pattern & Excess Capacity
Usage Pattern & Excess Capacity >Entry, stock, & drive-thru RTUs see high use pattern that is repeated across “identical” stores >One “identical” store halved its installed heating capacity and had no HI heat use increase Source: GTI 8
Slide 9: Gas Use & Weather
Gas Use & Weather >RTU equipped low-rise commercial buildings show correlation between heating gas use and outdoor temperature/heating degree days Source: GTI 9
Slide 10: Dedicated Outside Air System (DOAS)
Dedicated Outside Air System (DOAS) >Condition 100% OA for building ventilation >DOAS in retail stores (open 24/7) exhibit highest heating loads & longest runtimes for RTUs >Focus of follow-on condensing RTU demo Source: GTI 10
Slide 11: Big Box Retail Store Monitoring
Big Box Retail Store Monitoring 13 12 4 3 5 2 1 7 6 >200,000 sq ft big box 14 11 10 9 8 15 19 17 16 18 AHU 1 22 AHU 3 21 20 > Dozens of RTUs and 27 26 25 24 AHU 2 23 unit heaters 36 35 34 33 32 31 30 38 29 28 37 > 3 DOAS account for ~50% of gas usage in entire store >Annual gas use for a single DOAS
Slide 12: Key Takeaways So Far
Key Takeaways So Far >Very diverse heating runtimes for RTUs on a given building, but patterns emerge ─ Perimeter zone RTUs see longer runtimes and interior zone RTUs see shorter runtimes ─ RTU layouts in “identical” buildings show consistency in RTU runtime patterns with opportunity for selective h
Slide 13: Condensing Heating DOAS Pilots in Big Box Retail Stores in IL and MN
Condensing Heating DOAS Pilots in Big Box Retail Stores in IL and MN >Nicor Gas ETP ─ Baseline Winter 2010/2011 tests at IL store led to DOAS focus ─ Condensing DOAS tests Winter 2012/2013 with annual savings of ~2400 therms per DOAS Source: GTI >GTI ETP Consortium ─ Condensing DOAS tests began 3/20
Slide 14: Pilot Project at IL Store
Pilot Project at IL Store >3 step condensing heating module retrofit process over late September through mid-October 2012 1. Installation of condensate piping with neutralizer 2. Replacement of non-condensing heating modules 3. Completion of data acquisition system Source: GTI 14
Slide 15: Combustion Condensate System – from DOAS
Combustion Condensate System – from DOAS … >Plumbing slope To heat tape or minimum between not to heat tape … condensate ports that is the question! of heating module >Then vertical drop thru RTU base to conditioned space >Trap inside the Ensure heating module conditioned space design avoids standin
Slide 16: Combustion Condensate System – to Sanitary Drain
Combustion Condensate System – … to Sanitary Drain >Long runs to code required sanitary drain disposal >Acidic condensate neutralization is limited local code Take advantage of roof deck plumbing slope issue presently for condensate line! > Well established neutralizers from Replenish neutralizer co
Slide 17: DOAS Heating Module Retrofit
DOAS Heating Module Retrofit >Two (2) DOAS with two (2) heating modules each Source: GTI Source: GTI 17
Slide 18: Condensing Heating Module
Condensing Heating Module secondary >RTUs fundamentally (condensing) finned scale up residential tube heat exchanger condensing furnace heat exchangers, but ─ RTUs supply fans may run continuously during HVAC operating schedule and incremental pressure drop can create significant year round fan ener
Slide 19: Condensing RTU Thermal Efficiencies
Condensing RTU Thermal Efficiencies >Impacted by ambient air temperature, especially when processing large outside air fractions >Lower dew point, saturated air exits from flue Source: GTI 19
Slide 20: Icing at Flues is Typical in Operation
Icing at Flues is Typical in Operation Residential Condensing Big Box Retail Store Condensing Furnace Flue in MN DOAS Flues in MN Source: GTI 20
Slide 21: DOAS Net Operating Cost Savings/Year – for IL Store
DOAS Net Operating Cost Savings/Year – for IL Store Gas savings 2400 therms (11%) with 1285 kWh of added fan electricity for an annual net energy savings of $1444 @ $0.65/therm gas and $0.09/kWh High Efficiency DOAS Net Operating Cost Savings Assumptions inputs Net Annual Energy Cost Savings positiv
Slide 22: DOAS Payback Economics – for IL Store
DOAS Payback Economics – for IL Store Based on installed cost premium of $6085 for condensing DOAS and condensate system, plus a projected annual neutralizer maintenance cost of $65 for calcium carbonate replenishment, a simple payback of 4.4 years is estimated High Efficiency Heating Module DOAS Pa
Slide 23: More Key Takeaways
More Key Takeaways >Higher RTU runtimes key to generating high net operating cost savings for high efficiency payback >DOAS provides best early market payback scenario ─ “big box” retail accounts with established DOAS vendors ─ high heating degree day (HDD)/heating load locations >Mainstream condens
Slide 24: Major HVAC Manufacturer Perspective - Dick Lord, Carrier
Major HVAC Manufacturer Perspective - Dick Lord, Carrier Source: CEE, www.cee1.org/cee/mtg/10-11mtg/index.php3 24
Slide 25: Major HVAC Manufacturer Perspective - Dick Lord, Carrier
Major HVAC Manufacturer Perspective - Dick Lord, Carrier Source: CEE, www.cee1.org/cee/mtg/10-11mtg/index.php3 25
Slide 26: Condensing RTU Market Situation
Condensing RTU Market Situation >Non-major, second tier HVAC companies introducing product lines and provide early market entry point ─ Dedicated outside air systems (DOAS) ─ Applied by some key “big box” retail accounts >Major HVAC companies on the sidelines for now, but introducing staged blowers
Slide 27: Current Active Manufacturers
Current Active Manufacturers Manufacturer Availability Heating Module Specifications w/Hot Link (subject to change) 90%TE, 100 – 1,400 MBH input, 15:1 turndown, 1,000 to 44,000 CFM Engineered Air now www.engineeredair.com/index.php/our_products/category/indirect-fired#djx-series (DJX Series products
Slide 28: What the Future Holds
What the Future Holds … >Condensing heating RTUs ─ challenging market development from 100 to 30% OA > with current high equipment cost premiums > and low natural gas prices in US/Canada ─ logical market development will see progression in cost effectiveness to lower %OA RTUs over time ─ < 30% OA wi
Slide 29: Expanding Condensing RTU Offerings
… Expanding Condensing RTU Offerings >One manufacturer responding to the lower OA% challenge by providing condensing heating RTU product lines for the full (100 to 0) %OA spectrum ─ YDMA (~100 to 60% nominally) ─ YDHA (~60 to 30% nominally) ─ YDSA (~30 to 0% nominally) Source: Reznor 29
Slide 30: Other Condensing Product Offerings
… Other Condensing Product Offerings >Duct furnaces Source: Heatco ─ stand-alone or ─ furnace for RTU >Unit heaters Source: Modine ─ Manufacturing, warehousing, automotive, retail buildings >Wall furnaces/hearths ─ multifamily (rentals), home additions Source: Empire >Thru-the-wall furnace/AC ─ mult
Slide 31: Bibliography
Bibliography >Kosar, Douglas, et al. 2014. Field Monitoring of Rooftop Unit (RTU) Heating Runtimes and Gas Usage for Selected Commercial Buildings (NY- 14-C084). ASHRAE Papers CD: 2014 ASHRAE Winter Conference. Atlanta: ASHRAE. >Kosar, Douglas, et al. 2013. 1001: High Efficiency Heating Rooftop Unit
Slide 32: Sponsor Acknowledgements
Sponsor Acknowledgements >Utilization Technology Development (UTD) www.utd-co.org >Nicor Gas Emerging Technology Program www.nicorgasrebates.com/emerging >GTI Emerging Technology Program http://www.gastechnology.org/Expertise/Pages/ Emerging-Technology-Program.aspx and CenterPoint Energy, Union Gas,
Slide 33: Contact Information
Contact Information Douglas Kosar Senior Institute Engineer Building Energy Efficiency Gas Technology Institute 1700 S. Mount Prospect Road Des Plaines, IL 60018-1804 Office Phone: 847/768-0725 Office Fax: 847/768-0916 Cell Phone: 847/312-1398 E-mail: douglas.kosar@gastechnology.org Web Site: www.ga
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