www.Polar-Star.us Contact: Cliff Lyon 801.895.2977 USA

60 Patents112 Pending

...Worldwide

M.S., Moscow Institute of Physics and TechnologyPh.D., U.S.S.R. Academy of Science, Moscow 1974D.Sc., Physics and Mathematics, U.S.S.R. Academy of Science, Chernogolovka 1983

Publishing:Physics of IcePhysics of SemiconductorsOver 150 scientific publications

A team of physicists and engineers at Dartmouth College led by Dr. Victor Petrenko have unlocked the secrets of ice and perfected a number of ways to make ice work for us instead of against us.

(See video interview)

Dr. Victor F. Petrenko Go to websiteDirector, Ice Physics Research LabThayer School of EngineeringDartmouth College, Hanover, NH USA54 patents, 116 pending worldwide

Photo Courtesy of Gary Braasch. All Rights Reserved

Premise Ice Making

It takes almost as much energy to release ice from the tray as it does to freeze itPETD Ice Makers use 40% less energy

Energy consumption

Commercial refrigerators retrofitted with PETD evaporators use up to 25% less energy

Premise: Refrigerator

Energy consumption

Watch evaporators defrost in seconds (video)

Case Study: Refrigerator

Cost Day YearExisting evaporator 5.76 2,102PETD Evaporator 4.31 1,575

*Energy Cost @ .12 cents/kWhr)

PETD saves $525 dollars per year, per unit.

25% less energy

Electricity Cost Per Year See Video

PETD-I

PETD concentrates a “smart,” precise, high power pulse to the ice/substrate interface for between .01 - 4 seconds to heat a minimal layer of interfacial ice to just above the melting point causing the ice to slide off a resulting thin water film.

"An ice surface has a high electric charge. Ice doesn't simply cake onto surfaces, it bonds in three ways: via the hydrogen atoms themselves, via an electrostatic bond caused by the current and via comparatively weak van der Waals forces.

There is no surface coating which can suspend those three forces. That is why the search for ice-phobic coatings has failed. PETD melts just a few microns of the ice interface and gravity does the rest." - Dr. Victor Petrenko

SPECIAL NOTE: On Nov 16, 2010 PETD technology was named one of five innovation award winners of the ‘GE ecomagination Challenge: Powering the Grid’ For wind turbine blade deicing.

Pulse Electro-Thermal Deicing (PETD) (technical paper)

Evaporators

PETD evaporators are two to 10 times smaller, less expensive and up to 35% more efficient. Since no frost can accumulate, evaporators can be designed without consideration for frost and ice buildup.*

A PETD Evaporators self-defrost in 3 to 45 seconds vs. 15-60 minutes for conventional evaporators.

● Increased food shelf-life● Increased appliance reliability

Click to watch video

*Air Flow between fins is the primary factor in cooling efficiency. As frost/ice forms, Air Flow Area is reduced exponentially.

Refrigeration Overview

To get rid of frost, refrigeration evaporators are heated by an extremely inefficient and outdated method that makes the whole system run inefficiently. Refrigeration coils are built to accommodate the buildup of ice while operating. This reduces the heat exchange efficiency and causes compressors to run for longer periods of time which greatly increases the amount of energy required to provide the same amount of cooling.

PETD Savings

Display-case specifications used: Refrigerant temperature: Te = 26F = -3.33°CCondenser temperature: Tc = 104F = 40°CEvaporator air inlet temperature: Tair = 42F = 5.55°CTD = Tair - Te = 8.88°CCompressor isentropic efficiency: h = 75%Superheat: 5°C

= 0.0338 in%COP(272, 0, 5, 313.15, 0, 0.75, 0 - COP(271, 0, 5, 313.15, 0, 0.75, 0)COP(271, 0, 5, 313.15, 0, 0.75, 0)

Increasing the temperature by up to TD/2 = 8.8°C/2 = 4.4°C, improves energy saving for refrigeration system alone by 4.4 x 3.338 % = 14.87%. In the low-temperature cases an expected energy saving is up to two times less, about 8% to 10%, depending on a particular case specifications. In lower-temperature scenarios the energy saving up to 25% due to much shorter PETD defrost-cycle.

Fig 1, COP vs. evaporating temperature in °C at different condensing temperatures, 25° C, 40° C and 50° C.

Example of energy savings for a fresh-food display case

Calculations of 1°C change on relative change of COP: Thus, the energy saving is 3.38% per 1 degree °C increase in the evaporator temperature.

Dupont Duprex 3.0

Applications span all residential, commercial and industrial cooling systems

● Ice makers ● Refrigerators● Air conditioners ● Food displays ● Transportation containers● Heat pumps ● Dehumidifiers

Any cooling device!

Refrigeration Applications

See PETD in action-click

State of Technology