WHAT IS THE DIGI- RTU The Digi-RTU is a Heating, Ventilation, and - - PowerPoint PPT Presentation

▶
what is the digi rtu
SMART_READER_LITE
LIVE PREVIEW

WHAT IS THE DIGI- RTU The Digi-RTU is a Heating, Ventilation, and - - PowerPoint PPT Presentation

Sep 18, 2023 48 likes •292 views

WHAT IS THE DIGI- RTU The Digi-RTU is a Heating, Ventilation, and Air Conditioning (HVAC) rooftop unit control kit that is both a demand management and energy usage device. It is designed to improve the energy efficiency and demand

slide-1
SLIDE 1
slide-2
SLIDE 2

WHAT IS THE DIGI-RTU™

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

The Digi-RTU is a Heating, Ventilation, and Air Conditioning (HVAC) rooftop unit control kit that is both a demand management and energy usage

  • device. It is designed to improve the energy

efficiency and demand requirements of a rooftop unit as well as solve the humidity, common noise, and frequent on/off issues of a rooftop unit through modulating the capacity of a rooftop unit to match the cooling or heating space requirements.

slide-3
SLIDE 3

DIGI-RTU PERFORMANCE RECOGNITION American Public Power Association’s 2011 DEED Energy Innovator Award.

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

slide-4
SLIDE 4

DIGI-RTU ADDRESS ALL PNNL1 FOUR AREAS OF ROOFTOP UNITS ADVANCED CONTROLS

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

  • Integrates air-side economizers
  • Controls supply fan speed
  • Controls compressor capacity
  • Manages Demand-Controlled Ventilation, CO2
  • Demand Response signal enabled
  • Fault Detection via existing BAS, IP thermostat or

utilizing Digi-SFT

1Department of Energy's Pacific Northwest National Laboratory

http://www.pnnl.gov/main/publications/external/technical_reports/PNNL-20955.pdf

Addresses ALL Four PNNL Recommendations for Advanced Controls of Rooftop Units

slide-5
SLIDE 5

HOW THE DIGI-RTU WORKS

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

By intercepting heating and cooling calls, the Digi-RTU’s patented technology manages the compressor and fan speeds to match the space requirements. As a result space temperature and humidity are best managed.

DIGI-RTU KIT

slide-6
SLIDE 6

MAIN APPLICATIONS

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

– Package rooftop units, water and air source heat-pumps, split units – HVAC rooftop units between 3 to 30-ton – Up to four cooling stages – Up to two heating stages – Scroll & reciprocating compressors – Existing space thermostat and BMS

slide-7
SLIDE 7

DIGI-RTU ADVANCED CONTROLS FUNCTION

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

Modulating mechanical HVAC equipment to better match space

  • perating requirements is the accepted industry standard

Modulating fan and compressor is the energy efficiency strategy for all climate zones

  • Cool and hot/dry climates … increased free cooling
  • Cool and wet climates … humidity and moisture control

Economizer Integration

  • Integration and management of the existing economizer
  • Extends existing economizer range by 30%

Fan Speed Control

  • ON mode - average fan savings are greater than 85%
  • AUTO mode - average fan savings are 70 – 80%
slide-8
SLIDE 8

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

Demand Controlled Ventilation, CO2

  • CO2 sensor into the return air duct integrated with the

economizer satisfies ASHRAE 62.1 and CA Title 24 air quality requirements Fault Detection

  • Digi-SFT provides fault detection diagnostics and notification
  • r
  • Digi-RTU communicates with the existing BAS or IP enabled t-

stat for diagnostics and notification Demand Response

  • The Digi-RTU is subordinate to the existing T-stat or BAS

system responding to all space /building cooling and heating requirements

  • The load-limit factor for the rooftop unit is sent through the

BAS to the Digi-RTU, and can range from 50-100%

DIGI-RTU ADVANCED CONTROLS FUNCTION

slide-9
SLIDE 9

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

DIGI-RTU ADVANCED CONTROLS FUNCTION

Existing Building EE Strategies, Platform & Equipment

  • Communicates with existing BAS platforms and existing installed

thermostats; programmable, IP etc.

  • Integrates with the original equipment HVAC controller
  • Mounts inside the HVAC rooftop unit

Compressor Optimization

  • Conforms to original equipment manufacturer recommendations

for speed reduction down to 45Hz

  • Programmed logic provides soft start & stop of the compressor
  • Extended compressor life and lowered lifecycle costs
  • Compressor modulation savings are double fan power savings

for a significant portion of the United States climate zones

  • Peak Demand savings of 4 – 5kW for an average 10-ton rooftop
slide-10
SLIDE 10

BENEFITS OF USING A DIGI-RTU OPTIMIZER

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

For Utility Companies:

– Lowers peak demand up to 65% – Reduces kWh usage up to 65% – Decreases carbon emissions – Scalable, 3-hour install time

For Building Owners and Tenants:

– Reduces electricity consumption and costs – Better maintains space humidity and temperature which decreases comfort complaints – Reduces compressor on/off cycling up to 75%, and reduces maintenance cost – Reduces HVAC equipment noise in occupied space

slide-11
SLIDE 11

OMAHA, NE

slide-12
SLIDE 12

DIGI-RTU CASE STUDY – PHARMACEUTICAL DISTRIBUTION CENTER

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

70% kW decrease

  • 20

20 40 60 80 100 10 20 30 40 50 60 70 80 90 100 9/18 10/18 11/17 12/17 1/16 2/15 3/17 4/16 5/16 OAT (F) Power (kW) Date Without Digi-RTU With Digi-RTU OAT

Measured Power Consumption and Ambient Temperature

Pre - blue Post - red Ambient temperature 5-minute intervals

slide-13
SLIDE 13

DIGI-RTU CASE STUDY – PHARMACEUTICAL DISTRIBUTION CENTER

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

85% kWh decrease

Pre blue Post red 5-minute intervals

10 20 30 40 50 60 70 80 90 100 30 40 50 60 70 80 90 Power (kW) OAT Without Digi-RTU With Digi-RTU

Comparison of Measured Power Consumption with and without Digi-RTU

slide-14
SLIDE 14

SAN DIEGO

slide-15
SLIDE 15

DIGI-RTU CASE STUDY – OFFICE SPACE

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

February - March 2014

43% kW decrease

Measured RTU Power for One Minute Interval

Pre blue line Post green line Ambient temperature red line

slide-16
SLIDE 16

DIGI-RTU CASE STUDY – OFFICE SPACE

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

February - March 2014

71% kWh decrease

Pre blue line Post green line

Daily Electrical Energy Consumption; Pre (blue ) and Post (red ) vs. Ambient Temperature

slide-17
SLIDE 17

SAN ANTONIO TX

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

slide-18
SLIDE 18

SEPTEMBER – OCTOBER 2012 BIG BOX RETAIL

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

Two weeks with and two weeks without

29.5% kW decrease

10 20 30 40 50 60 70 80 90 100 1 2 3 4 5 6 7 8 8/27 8/28 8/29 8/30 8/31 9/1 9/2 9/3 9/4 9/5 9/6 9/7 9/8 9/9 9/10 9/11 9/12 9/13 9/14 9/15 9/16 9/17 9/18 9/19 9/20 9/21 9/22 9/23 9/24 9/25 9/26 9/27 9/28 9/29 9/30 10/1 10/2 10/3 10/4 10/5 10/6 10/7 OAT, Deg F kW Before After AVG-OAT

slide-19
SLIDE 19

0.5 1 1.5 2 2.5 3 3.5 4 4.5 kWh 9/23/12 (OAT = 78 F; weekend; after install) 9/26/12 (OAT = 80 F; weekday; after install) 9/9/12 (OAT =79 F; weenkend; before install) 9/11/12 (OAT = 79 F; weekday; before install)

DIGI-RTU INSTALL ASHRAE #2 BIG BOX RETAIL

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

Two days with and two days without

74% kWh reduction

slide-20
SLIDE 20

VERMONT

slide-21
SLIDE 21

BURLINGTON ELECTRIC – STUDY

Office Building

1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000 9,000 kWh

Metered Savings = 65%

W/O Digi-RTU With Digi-RTU

65% kWh reduction

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

  • Equipment sub-metered
  • Two weeks pre
  • Two weeks post
  • IPMVP

20 40 60 80 100 4-Aug 9-Aug 14-Aug 19-Aug 24-Aug 29-Aug 3-Sep 8-Sep

  • Avg. OAT

Date

Without Optimizer With Optimizer

slide-22
SLIDE 22

EFFICIENCY VERMONT - STUDY

Distribution Center

10,000 20,000 30,000 40,000 50,000 60,000 70,000 kWh

Metered Savings = 68%

W/O Digi-RTU With Digi-RTU

68% kWh reduction

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

  • Equipment sub-metered
  • Two weeks pre
  • Two weeks post
  • IPMVP

10 20 30 40 50 60 70 80 20-Sep 22-Sep 24-Sep 26-Sep 28-Sep 30-Sep 2-Oct 4-Oct 6-Oct 8-Oct 10-Oct 12-Oct 14-Oct 16-Oct 18-Oct

  • Avg. OAT

Without Optimizer With Optimizer

slide-23
SLIDE 23

DIGI-RTU CONCLUSIONS

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

Digi-RTU is able to:

– Reduce peak demand up to 65% – Reduce consumption up to 65% – Improve room humidity management – Improve room temperature management – Reduce compressor cycling – Reduce maintenance costs – Reduce equipment noise

slide-24
SLIDE 24

4640 South 59th Street | Omaha, NE 68117 402.502.2340 | bes-tech.net

Bes-Tech, Inc. 4640 S 59th Street Omaha, NE 68117 402.502.2340 BES-TECH.NET