UV-C LED Devices and Systems:

Current and Future State

IUVA Americas ConferenceFebruary 2018

Authors: Molly McKain

Dr. Jennifer Pagan, Oliver Lawal, Jim Cosman

What are Light Emitting Diodes (LEDs)?

Wafer with over 20,000 LEDs

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Detailed view of an LED Individually packaged

LED Chip

Lens

Outer Package

Submount

LEDs are High Power Density Light Sources

More photons per surface area

Smaller lamp footprint

Smaller UV system

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Small is Problematic for Hg

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Parameter Brand Ushio Philips Philips2 Ushio3 AquiSense

MPN (Part No.) 3000022 PL-S5W/TUV 325126 3000304 PAQC-1

Lamp Architecture T7 Twin-Tube Twin-Tube Twin-Tube PCB

Base Type E17 G23 G23 G23 PCB

Life Hours (Hours) 3,000 8,000 8,000 8,000 10,000

Wattage (Watts) 3 Watt 5.5 Watt 9 Watt 9 Watt 8 Watt

Voltage 10.5 34 60 59 12

Current (Amps) 0.3 0.18 0.17 0.18 0.35

UV-C Output (Watts) 0.16 1.1 2.3 2.4 0.18

Wavelength 253.7 nm 253.7 nm 253.7 nm 253.7 nm 270-280 nm

Length (mm) 63 85 145 145 20 X 30

Diameter (Inches) 20 25,4 28 28 2.6 (height)

WPE 5% 20% 26% 27% 2%

Smallest Hg lamp is double the size of LED lamp

LED lamp includes drive and monitoring circuitry

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Potential (Application Specific) Additive Benefits

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Lamp Warm-Up Time

UV-LED Gas Discharge

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Lamp Aging with High On-Off Cycling (over 10/day)

UV-LED Gas Discharge

Lamp Heat and Light Direction – Fouling Potential

Historical UV-C LED Device Efficiency

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Current Best-In-Class Device

• Wall Plug Efficiency 4%

• UV Intensity Output 70mW

• Lifetime L70 10,000 hours

Best-in-Class Single DevicesSource: Dept of Energy & Internal AquiSense Measurement Data

Source: Internal AquiSense Measurement Data

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Why System Design Matters

• The design of the system is just as important as the LEDs within it.

• Mercury lamps are 15-35% efficient so they can be pared with a moderately efficient reactor.

• UV LEDs are less than 5% efficient so they must be paired with a highly efficient reactor.

Example Applications Under Development

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Transportation

• RV & Boating

• Automotive

• Aviation (fuel systems & DW)

• Space (Habitats & Exploration)

Health Care

• HAI Control

• Dialysis

• Dental

Life Sciences

• Bio-pharma

• UPW

Commercial

• Food & Beverage Service

• Water Dispensers & Fountains

Residential

• POE

• White Goods

• Faucets

Defense/Emergency Response

• Personal Hydration

• Remote Treatment

Current Commercial Systems

• Commercially available UV-C LED systems are more common in sub 20lpm range

• Targeting small footprint, intermittent flow applications (not ideal for mercury gas discharge)

• Price point remains challenging

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Not competing with large scale Hg systems

Case Study: Commercial Steam Oven

• Problem: Pathogens in low temperature steam ovens

• Goals: Disinfect inlet water

• Key Design Parameters:

• 4-log target pathogen reduction

• Intermittent flow (6 sec On, 30 Sec off)

• Small envelope

• Warm environment

• Solution: PearlAqua Micro

• Met all design parameters

• Completed product robustness testing

• Volume Production Start Date Q3 2017

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Haitz’s Law – So Far, So Good

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“For every decade of development LED Optical Power increases 20x and cost/lumen falls by 10x”

Implication for 2026 is 1.4 Watt per LED at 0.1 $/mW

Reported Performance Records (Research)

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Research grade UVC LEDs are already more efficient than some UV lamps

2018 will debut products in excess of 100mW per single chip

Benchmark:

Typical Medium Pressure,

Hg lamp

Implications for Future Commercialization

4% best-in-class commercial20% lab devices

Novel LED reactors have shown higher

efficiencies than conventional lamp reactors

If LEDs become ultra-low cost,

then efficiency has a lower factor

LEDs have specific characteristics that can

lower Operating Cost

LED Devices Increase Efficiency

LED Devices

Lower Cost

Refined System

Engineering

Larger Systems

Municipal Water Treatment

Piloting Started in 2017

Expect the first municipal system installations in 2019

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Source: Typhon Treatment Source: MetaWater

Surface & Air Applications

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Distributed, batch applications progress to centralized continuous applications

Source: SealShield

Space Habitats & Exploration

• ISS currently has 88% water recycling efficiency

• Over 92% required for long term exploration and closed habitat

• UV-C LED systems playing key role in process solution

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UV-C LED technology will help us get to, and live on Mars

Strong correlation to terrestrial treatment solutions

Summary

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Molly McKain - Applications Engineer

AquiSense Technologies

molly.mckain@aquisense.com

LEDs offer some application specific advantages

Evaluation on-going in large range of applications

High volume commercial applications exist

If Haitz’s Law continues, larger systems will follow