eeweb pulse - issue 38, 2012

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March 20, 20

Joe KeatingInfnite Power Solutions

Electrical Engineering Commun

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TABLE OF CONTENTS

Joe Keating 4Infnite Power Solutions

Self-Powered Maintenance-Free 10Sensor Node for Smart PhonesBY JOE KEATING

Featured Products 12

Timing the Communication Channels

of an Encoder to a Brushless MotorBY JIM MILLER WITH QUANTUM DEVICES, INC.

The Aquarius MRE System: A Marine 17

Renewable Energy Solution forModern ShipsBY GREG ATKINSON WITH ECO MARINE POWER

RTZ - Return to Zero Comic 21

Infinite Power Solutions Targets Bluetooth Smart Devices Using THINERGY MECs.

Interview with Joe Keating - Senior Director of Applications Engineering

Timing is everything--from a car engine to an optical encoder.

How past and present energy technologies are integrated for a “greener” power solution.

14











































INTERVIEW

Infnite Power SolutionsHow did you get into electrical engineering andwhen did you start?

I graduated with a degree in Electrical and Computer

Engineering in 1992 and have been working in and

around the field of electronics ever since.

Can you tell us about your work experiencebefore becoming a Senior Director ofApplications Engineering at Innite PowerSolutions?

I have a diverse background in consumer, industrial and

commercial product development. I have also spent

quite a bit of my career working on battery development,

battery applications, and testing.

Who has inuenced you the most throughoutyour career?

I have benefited from many mentors throughout my career. They have mostly been peers who have exhibited

talents and interest in their respective fields, leading them

to produce successful designs, products and solutions.

By working with them and observing their design and

development methods, I have been able to build core

design and development skills that have been valuable

across a range of different markets and industries. I

have also benefitted from many opportunities to work

JoeKeating Joe Keating - Senior Director of Applications Engineering






































INTERVIEW

in fields that are well outside of the

traditional electronics designer’s

duties, such as manufacturing

management, quality systems

development, and direct sales and

marketing activities.

What are your favoritehardware tools that you use?

I always start with a trusty Fluke

meter, preferably a model 87 or

newer. Microchip and TI, among

others, have traditionally produced

excellent low-cost embedded

development tools that include

circuit emulation, which I think is

critical in any efficient embedded

system development flow. Any

ICE tool is usually a great thing to

have. Also, an oscilloscope, power

supply, soldering iron and a link to

the Digi-Key site are all essential

tools.

How about your favoritesoftware tools?

I’m a huge fan of Altium. We

converted to their tools last year andhaven’t looked back. For a small to

mid-sized electronics design and

development firm, it’s my top pick

for PCB schematic capture and

layout. I also always have a copy of

5SPICE ready to go.

What is on your bookshelf?

The Art of Electronics by Horowitz

and Hill, Modular Series on Solid

State Devices, Volumes 1-4, RF Design Guide by Vizmuller,

Numerical Methods for Engineers

by Chapra and Canale, and a

plethora of battery books.

Do you have any tricks upyour sleeve?

Don’t underestimate the design

and testing time required when

developing a battery-powered

system for a product. Batteries, in my

experience, are akin to living things

and have many caveats and quirks

that require careful consideration

before being included in a design.

A good rule of thumb, especially

when working with a rechargeable

battery, is to get in touch with the

technical support team of the

selected battery manufacturer as

early as possible in the design

process. This can eliminate several

board spins and will help to get your

product out in time.

What has been your favoriteproject so far?

I developed a multichannel battery

cycle testing system for an extremely

high-power lead acid battery that

we were bringing to market. We

produced a cell that could be built

into a 1kg battery pack that could

fit in your hand and was capable of

cold starting a Corvette. The testing

system required developmentfrom the board level through to the

company-wide network in order to

provide real time testing data to our

R&D and manufacturing teams.

Do you have any noteworthyengineering experiences?

I have a few patents and have

been asked to present at various

conferences and panels. I’ve been

fortunate to have participated in anIPO event for a start-up company in

which I was the fourth employee.

Do you have any experientialstories you would like toshare?

I did have a close call when working

on a hybrid battery I designed for a

prototype HEV being tested by one

of the “big three” in Detroit back in

the 90s. We were doing acceleration

runs to test the peak power output of

the combined system. As the battery

engineer, I was asked to participate

in the testing. The test vehicle

was based on a mini-van. The two

primary engineers were in the front

seats with full crash harnesses. The

components for the HEV took up the

passenger area, so I was sitting on

a foam block between the two front

seats, holding a laptop that was

collecting data from the test runs.

We were zipping up and down an

access road behind the engineeringfacility that was also used by trucks

to bring in inventory to a nearby

Home Depot. We were focused on

the laptop screen when I looked

up and saw the word “PETERBILT”

coming straight at me. Fortunately,

the engineer driving the van had

pretty good reflexes and swerved

out of the way of the oncoming

tractor trailer in time to keep me

from becoming a hood ornament.

How do you provideapplication support anddevelopment for new,innovative, thin lm Lithiumbattery technology?

As I noted above, we try to get the

applications team involved at the

beginning of the engagement with

every customer. Batteries are a

technical sale and require close and

thorough support in order to make

sure that the product is successful.

Because we have been working

in this space for many years, our

applications engineers have many

tricks and design insights available

to ensure that the electronics or

application requirements are

served by the proper battery and





















































































































































INTERVIEW

power management solution.

Additionally, we have accumulated

world-leading experience in the

development of self-sustaining

or autonomously powered micro-

electronic solutions. To support

this, we have created a team of

engineers and technicians that

can provide any level of technical

support from documentation to

entire product design depending

on a given customer’s needs.

Can you tell us about yourindustry experience inconsumer electronics, battery

design and manufacturing,textile equipment and optics?

I guess the thing I’m most aware of

after working across a diverse set

of industries is that it is important

to keep an eye on the bigger

picture involving the customer.

A strategy of providing solutions

that meet customer requirements

should override most if not all other

concerns within the development

process. Driving the strategy requires a strong, clear and focused

vision regarding the product or

service that is being provided.

I have seen too many products

limp into production because the

goals weren’t clear. This resulted

in solutions that cost the company

too much to produce and support.

Commitment to setting up and

adhering to specific product feature

and quality targets is paramount

to succeeding in any industrial

or technology market. Strong

engineering leadership committed

to this process always yields

positive results when the products

hit the market.

What are some of the newtechnologies you are workingon at Innite Power Solutions?

IPS is the world leader in developing

thin film, solid state rechargeable

batteries. We are also involved in the

development of new power source

technologies for microelectronics,

specifically in the areas of wireless

sensors, real-time clocks/memory

backup and powered cards.

Wireless sensors are undergoing a

revolution in that they are becoming

the keystone technology in an

increasingly sensor-aware world.

To date, the major stumbling block

for wireless sensors has been the

IPS is very customer

focused with a

dedicated and

highly experienced

applicationsengineering team to

help our customers

plan their design and

properly implement

our battery into

their system.

battery. Primary (or non-

rechargeable) batteries have

traditionally been used as the power

source for wireless sensors, such

as remote temperature or security

sensors found in buildings. This has

greatly limited the adoption of these

technologies because the cost

required to change the batteries in

a given facility will become onerous

as the number of sensors increases.

In addition, dead batteries imply

that the sensor will no longer

function properly. Rechargeable

solutions such as Lithium Ion or

Lithium Polymer batteries do not

have sufficient cycle life or longevity

to provide power to sensor

systems for the required minimum

functional life of most commercial

or industrial sensors. This results

in maintenance costs that oftenmake wireless sensors impractical.

THINERGY® Micro-Energy

Cells (MECs) from Infinite Power

Solutions (IPS) solve this problem

by providing an operational lifetime

in excess of 15 years, and cycling

performance that is 10–100 times

better than most other rechargeable

battery technologies. As a result,

we can combine our MECs with

energy-harvesting devices suchas solar panels, thermoelectric

generators, piezoelectric devices

or RF-harvesting systems to provide

a power source that will gather

and store ambient energy from

the environment surrounding the

sensor. This allows the sensor

to operate for decades without

any maintenance or power

failure events. IPS has developed

technology around this concept that

includes some of the world’s lowest

power sensor or wireless node

solutions. We have collaborated

in the development of several new

ultra-low power energy storage

and management IC solutions

such as the MAX17710 from Maxim

Integrated Products, the LTC4071

from Linear Technologies and the







































































































































INTERVIEW

BQ25504 from Texas Instruments.

These parts all provide simple

and ultra-efficient energy storage

management solutions, enabling

designers to combine an energy

harvesting device such as a small

solar panel with a THINERGY

MEC to power an RF-based sensor

node enabling a network of small,

maintenance free, robust sensors.

This revolution in remote power

delivery will vastly increase the

deployment of wireless sensors

allowing buildings to operate more

efficiently, machinery to become

more reliable and facilities to

become more secure, just to namea few applications.

Can you tell us more aboutInnite Power Solutions?

IPS is a clean technology growth

firm that manufactures its solid-

state energy storage products in

a custom-built facility in Littleton,

Colorado. IPS is a small but growing

R&D and manufacturing company

that leads the industry in bringingthe world’s thinnest, most powerful

and longest-lasting batteries to the

micro-power market. By providing

solutions into a region within the

energy storage market where there

have not previously been suitable

solutions, IPS will enable potentially

massive new markets and products

to be developed.

How does Innite PowerSolutions continue tobe a global leader inmanufacturing solid-state,rechargeable, thin-lm micro-energy storage devices forembedded applications?

IPS continues to maintain its solid-

state battery industry leadership in

a variety of ways. First and foremost,

THINERGY MECs outperform

competing small battery solutions in

all performance metrics, especially

when it comes to operating

temperature range, discharge

rate and cycle life. IPS also has a

formidable intellectual property

portfolio with numerous granted

U.S. and international patents that

are vital to the manufacture of solid-

state thin-film batteries. Continued

Research and Development has

also been a key differentiator for IPS

as it continues to develop advanced

packaging and manufacturing

methodologies, as well as

developing new solid-state battery solutions with unprecedented

energy density.

...IPS will introduce

new, low-cost

rechargeable battery

solutions withindustry leading

energy density that

will displace a variety

of common battery

types in use today.

How has the companychanged since itsfounding in 2001?

In the early days, IPS fabricated

its thin-film batteries on a thin

ceramic substrate, much like those

developed at Oak Ridge National

Labs. While ceramic is an ideal

surface for depositing thin-films

and for proving the virtues of solid-

state battery performance, it was

not ideal in terms of material cost

or for end users who wanted a

thinner, more flexible solution. In

2007, IPS began to fabricate cells

on thin (50µm) metal foil substrates

and quickly became the envy of

the solid-sate battery industry.

No other manufacturer has been

successful fabricating such cells

on this low-cost metal foil substrate

which provides advantages in high-

temperature processing during

fabrication, in addition to thinness,flexibility, hermeticity, and overall

simplicity.

What is the work culture like atInnite Power Solutions?

IPS is very customer-focused with a

dedicated and highly experienced

applications engineering team

to help our customers plan their

design and properly implement our

battery into their system.

What direction do you seeyour business heading in thenext few years?

IPS continues to lead the small

rechargeable battery industry in

all performance metrics. Over the

next few years, IPS will introduce

new, low-cost rechargeable battery

solutions with industry leading

energy density that will displace a variety of common battery types in

use today.

What challenges do youforesee in our industry?

Well, it’s hard to see into the future,

but generally speaking, adoption

of new or improved technologies







































































































































INTERVIEW

is often hampered by the slow

or conflicting development of

standards. This will be a continuing

effort for IPS to work with the

various players within the wireless

sensor and powered card markets

to attempt to unify or condense

the many proposed and existing

standards that are available today.

As certain manufacturers begin

to dominate in these markets,

their selected standards will

gain acceptance across a wider

audience. At this time, there are

many different standards options

in our target markets that cause

confusion and increase the risk for

our end customers as they attempt

to bring solutions to their customers.

What are some of yourhobbies outside of work anddesign?

I ski, mountain bike and race

motorcycles. It’s Colorado, so

there’s a lot to do with the 300+

days of sunshine we get!

Is there anything that youhave not accomplished yet,that you have your sights onaccomplishing in the nearfuture?

One of these days I hope to startup a new company, but for now

I’m focused on getting IPS and

our very exciting solid-state battery

technologies out to the mass

market!

http://bit.ly/nKLRXo









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Renewable EnergyInverters

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PROJECT

Self-Powered

Maintenance-FreeSensor Node forSmart Phones

By Joe Keating

With the introduction of the new

Bluetooth 4.0 standard that will

soon be available in many portable

devices such as phones and

tablets, comes a sub-feature known

as Bluetooth Low Energy (BLE).Traditional Bluetooth® devices

such as headsets draw a fairly

high amount of continuous current

requiring rechargeable Lithium

Polymer (LiPO) batteries that

provide sufficient energy and power

in order to maintain voice or data

streaming. However, for low power,

intermittent applications such as

temperature sensors, maintaining

a Bluetooth session tends to

require a great deal more energy

than is really necessary to support

low data rate transmissions. BLE,

on the other hand, can produce

thousands to millions of short, low

data rate wireless transactions

using the energy from a single

charge provided by a much smaller

battery. Devices incorporating this

low power BLE feature are known

as “Bluetooth Smart” devices.

The power consumption rates are

actually so low that extremely small

batteries can be used to power tiny,ultra-low power Bluetooth Smart

sensors that will communicate with

phones and phone-based apps

while being constantly recharged

with energy scavenged from the

surrounding environment (think

small solar panels, etc.). My

company, Infinite Power Solutions

(IPS), offers 4V solid-state batteries

known as THINERGY® Micro-

Energy Cells (MECs) that are

particularly well-suited for Bluetooth

Low Energy applications. To

address this emerging market, IPS

is working on a BLE based sensor

reference design.

By introducing this technology into

our handheld devices, low power

sensors can now be ubiquitous in

our personal environments and will

be able to communicate through our

phones, for example, to our friends,

families, doctors, etc., to provide

information such as security access,

activity, temperature or blood

pressure. The downside of adding

wireless sensors everywhere

has traditionally been the need

to replace batteries. Imagine

being trapped in a sea of devices

that constantly clamor for battery

replacement (anyone with children

can sympathize!). This is especially

problematic for biometric sensors

that could be installed to monitor

health and activity statistics forpeople under constant care. It will

be difficult to require Alzheimer’s

patients, for example, to change

batteries on their temperature or

activity sensors. Fortunately, the BLE

specification power requirements

are so low that for short transactions

such as communicating your

proximity to your desk (useful for

granting secure access to a work

station), an MEC can be maintainedin a full state of charge indefinitely by

harvesting microwatts from a small

solar panel installed on the sensor.

THINERGY solid-state MECs are

a great fit for this model in that

they have the ability to efficiently

store energy down to power levels

below 1µW and last for more than

15 years because of their extremely

low internal leakage rates and lack

of liquids or polymers. As a result,

the design of the sensor will be

radically changed. An over-mold or

potted enclosure can now be used

since the battery won’t wear out for

the lifetime of the product and will

never need to be changed. This

eliminates the need for the typical

“clamshell” style enclosure with a

battery door and separate battery

Infinite Power Solutions Targets

Bluetooth Smart Devices UsingTHINERGY MECs





















































































































PROJECT

contacts. Assembly steps are

eliminated along with a great deal of

material reducing cost. This results

in a very durable, fully enclosed

sensor module that will last for years

without any user maintenance.

Since the unit will be constantly charging from the embedded solar

panel, no further user intervention is

required.

As with all battery powered

designs, the power requirements

need to be addressed to figure out

how large the MEC and the solar

panel will have to be in order to

meet the user’s requirements. In

this case, our reference design

will be transmitting proximity using

RSSI (received signal strength

indication, a feature included in

the BLE specification) along with

temperature transmission onceevery five seconds. The following

image from Texas Instruments

shows the measured current used

during a single BLE transaction

using a TI CC2540 BLE SOC.

The scope settings used were

60mV per division with the time

scale at 400µs per division. A 10Ω

resistor was used in line with the

power source to measure the

current. By integrating the area

under the curve, the result is

24.5µAs for this single transaction,

which is the equivalent of 10.6mA

average current over a 2.3ms

period. Assuming that we are using

a 130µAh THINERGY MEC225,

which is 0.17mm x 1.6cm^2, more

than 19,000 transactions can be

made on a single charge. Of course

this doesn’t take into account the

sleep current between sessions.

Assuming that this sleep current

is 0.5µA or so, which is easily

attainable with today’s real-timeclocks and microcontrollers, you

can then calculate the average

current to be approximately

6µA, which results in 24 hours of

operating time on a single charge.

This also implies that an average

of 6µA needs to be supplied to the

unit from a solar panel to keep the

battery from running out. Getting

this amount of current is extremely

easy using even a very small andinexpensive solar panel.

The result will be a simple, mainte-

nance-free Bluetooth Smart sensor

that will directly communicate with

an iPhone (the iPhone 4S is the first

phone with BLE). A simple app

developed for the phone will allow

users to view or share information

from their environment to the web

or to other services, games or social

networks, opening up a whole new world of interactive applications.

i“Application Note AN092: Mea-

suring Bluetooth Low Energy Power

Consumption”, Sandeep Kamath,

Texas Insturments, 2010

Figure 1: BLE Transaction Current levelsi

Figure 2: Functional Block Diagram






























































































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A

lignment of optical encoder commutation

signals to a Brushless DC (BLDC) motor could

be thought of as being comparable to timingthe distributor on a car engine — the distributor tells

the spark plugs on the engine when to fire. In a similar

manner, the commutation channels of an incremental

encoder tell the amplifier or drive when to turn on the

windings in a BLDC motor.

And just like a car engine, if the timing is off, the motor

will run incorrectly, inefficiently, or not at all. If two of the

encoder commutation phases are accidentally reversed,

the motor will run backwards.

To time commutation channels of an incremental encoderto a BLDC motor, you will need to know which motor

winding corresponds to which encoder commutation

signal. This information is usually found in the motor and

encoder documentation.

As I am most intimately familiar with the Quantum

Devices series of encoders, the following steps are best

suited to those encoders, but should serve as a general

guide to timing any encoder.

Basic Steps:

1. One phase of the motor is energized, locking the

rotor into position.

2. The encoder is rotated to a given position, which is

usually the start of one of the commutation signals

(i.e., leading edge of U). This often corresponds with

the encoder’s index pulse.

3. The encoder is assembled to the motor and the shaft

is locked in place (via encoder set screws). The

encoder flex mount is not yet secured.

4. The motor winding is de-energized.

5. The Optical Encoder is powered.

6. The motor/encoder is back driven by another

motor and the two waveforms are displayed on an

oscilloscope. One waveform is back EMF from

the motor phase, and the other is the encoder

commutation channel.

Jim Miller Application/design Engineer

Timing the CommutationChannels of an

Optical Encoder Brushless Motor to a

























































TECHNICAL ARTICLE

Below the motor, back EMF and Encoder Commutation

(Hall) signals are shown. They have been separated for

clarity, when timing a motor,they will overlap.

Proper timing typically calls for aligning the zero volt

level of the back EMF sine wave with the edges of the

commutation signals. That level is shown in Figure 3 by

the red line.

8. Once alignment is achieved, the encoder flex mount issecured, locking in the phase relationship between the

motor and encoder.

About the Author

Jim Miller is employed with Quantum Devices Inc,

a leading manufacturer of optical rotary incremental

encoders. He plays a vital role in optical encoder design

and development.

Figure 1: Back driven motor set up

Figure 2

7. While the motor is rotating, the assembly is fine-tuned

by turning the encoder body to align the encoder

signal to the motor’s back EMF waveform.

Video of BLDC motor Back EMF to Optical Encoder

Commutation Timing.

Figure 3






























http://www.youtube.com/watch?v=HX8UbIg04N8






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high-current, single-output LDO specified for up to 3.0A of

continuous output current. These devices operate over an input

voltage range of 2.2V to 6.0V and are capable of providing

output voltages of 0.8V to 5.0V adjustable based on resistor

divider setting. Dropout voltages as low as 65mV can be

realized using the device.

The OCP pin allows the short circuit output current limit

threshold to be programmed by means of a resistor from the

OCP pin to GND. The OCP setting range is from 0.5A minimum

to 8.5A maximum. The resistor sets the constant current

threshold for the output under fault conditions. The thermal

shutdown disables the output if the device temperature

exceeds the specified value. It subsequently enters an ON/OFF

cycle until the fault is removed. The ENABLE feature allows the

part to be placed into a low current shutdown mode thattypically draws about 1µA. When enabled, the device operates

with a typical low ground current of 11mA, which provides for

operation with low quiescent power consumption.

The device is optimized for fast transient response and single

event effects. This reduces the magnitude of SET seen on the

output. Additional protection diodes and filters are not needed.

The device is stable with tantalum capacitors as low as 47µF

and provides excellent regulation all the way from no load to

full load. Programmable soft-start allows the user to program

the inrush current by means of the decoupling capacitor value

used on the BYP pin.

Applications• LDO Regulator for Space Application

• DSP, FPGA and µP Core Power Supplies

• Post-regulation of Switched Mode Power Supplies

• Down-hole Drilling

Features• DLA SMD#5962-11212

• Output Current Up to 3.0A at TJ = 150°C• Output Accuracy ±1.5% over MIL Temp Range

• Ultra Low Dropout:

- 65mV Typ Dropout at 1.0A

- 225mV Typ Dropout at 3.0A

• Noise of 100µVRMS from 300Hz to 300kHz

• SET Mitigation with No Added Filtering/Diodes

• Input Supply Range: 2.2V to 6.0V

• Fast Load Transient Response

• Shutdown Current of 1µA Typ

• Output Adjustable Using External Resistors

• PSRR 66dB Typ @ 1kHz

• Enable and PGood Feature

• Programmable Soft-start/Inrush Current Limiting

• Adjustable Overcurrent Limit from 0.5A to 8.5A

• Over-temperature Shutdown

• Stable with 47µF Min Tantalum Capacitor

• 18 Ld Ceramic Flatpack Package

• Radiation Environment

- High Dose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 krad(Si)

- SET/SEL/SEB . . . . . . . . . . . . . . . . . . . . . . . .86 MeV•cm2 /mg

FIGURE 1. TYPICAL APPLICATION FIGURE 2. DROPOUT vs IOUT

EN

PG

VIN

OCP

ROCP

220uF 0.1uF

PG

VIN

ISL75051SRH

BYP

ADJ

VOUT

GND

0.1uF 220uF

0.1uF

R1

R2

2.67k

4.7n

100pF

VOUTVIN

EN

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50

IOUT (A)

D R O P O U T V O L T A G E

( V )

+125°C

+25°C

+150°C

November 4, 2011

FN7610.1

Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2011

All Rights Reserved. All other trademarks mentioned are the property of their respective owners.

Get the Datasheet and Order Samples

http://www.intersil.com

http://bit.ly/nHxRhB














































































































































Wind & Solar Power at Sea

Wind power has been used by

ships as a means of propulsion for

thousands of years, but with the

advent of the steam and internal

combustion engines during the

Industrial Revolution, the use of sail

power fell away sharply around the

mid-19th century. Today however,

there is a resurgent interest in the

use of sails for commercial vessels

as shipping companies seek ways

to reduce fuel costs and comply

with new airborne maritime missionstandards.

Traditional flexible sails with rigging

are generally not suitable for large

commercial ships, however rigid

sails could be a practical way to

utilize wind power on modern

ocean-going vessels in order to

lower fuel consumption & reduce

noxious gas emissions.

Rigid sails are not a new concept

and designs vary widely. In the

1970s and 1980s, for example,

two ships in Japan were fitted with

curved rigid sails, and in the 1980s

Jacques Cousteau, Professor Lucien

Malavard and Dr. Bertrand Charrier

developed a turbosail which was

then fitted to the research ship,

Alcyone.

Both of these innovative conceptsreduced fuel consumption, however,

for a variety of reasons, rigid sails

have not yet gained widespread

acceptance.

Solar power is another renewable

energy technology also suitable

for ships. In recent years,

significant advances have been

made in terms of developing solar

panels that are lightweight, more

efficient and suitable for the harshmarine environment. A number

of commercial ocean-going ships

have already been fitted with solar

panels such as Nippon Yusen’s

(NYK) Auriga Leader.

At this stage, solar power alone

is unable to provide the energy

required for propulsion on large

ships. It can, however, be an

important alternative source of

power for on-board electricalsystems, thereby helping to reduce

fuel consumption and noxious gas

emissions.

The challenge for system designers

is to develop a solution for ships

that can tap into the power of the

wind and sun, yet be cost effective,

Greg Atkinson Director, Research & Development

The AquariusMRE System:

A Marine Renewable

Energy Solution

for Modern Ships















































































TECHNICAL ARTICLE

practical and safe for the crew or

vessel.

A Combined Wind & Solar

Power Solution for Ships

Unlike land-based renewable

energy solutions such as solar

and wind farms, the area or space

available on ships for installing wind

and solar power systems is quite

limited. Taking this into account,

it would appear advantageous to

develop a system that can use both

wind and solar power as energy

sources, and be able to harness it

via the same system.

The Aquarius Marine Renewable

Energy (MRE) System being

developed by Eco Marine Power

will achieve this by using rigid sails

and an array of solar panels.

The Aquarius MRE System™ (patent

pending) or Aquarius System™

will use this array of rigid sails and

solar panels to form a ship-based

renewable energy system. On large

ships, up to twenty rigid sails could

be installed whereas on smaller

vessels, just one or two sails would

be needed.

The Aquarius MRE System™ isnot intended to be a ship’s primary

source of propulsion. Instead,

the system is being designed to

work alongside other technologies

to reduce fuel consumption and

harmful gas emissions for a variety

of ships such as bulk carriers, oil

tankers and cargo ships.

Depending on the number, size,

shape and configuration of the rigid

sails, it is estimated that the system

will reduce a vessel’s annual fuel

consumption by up to 20 percent.

Aquarius MRE System™

Technology

Large commercial ships such

as bulk carriers and oil tankers

operate with a small crew, therefore

a renewable energy solution for

these types of vessels needs to be

automated.

To achieve this, an advanced

computer control system is being

developed so that the rigid sails

will automatically be positionedto adapt to the prevailing weather

conditions.

The rigid sails can be rotated to best

use the available wind, or if there is

no wind, then the solar panels or

cells will be able to collect solar

energy during the day. The solar

panels could be mounted on the

sails, or alternatively, they could be

mounted elsewhere on the ship.

In addition, the control system

will monitor the performance of

the system and provide a means

by which the crew can manually

control the rigid sails if needed

via command consoles. These

consoles can be located in a variety

of positions on-board the ship.

The computer control system will

also include a number of safety

features to prevent the sails or ship

from being damaged.

The Aquarius computer control

system will be based on the KEI

3240 Computer System developed

by KEI System Ltd. of Osaka, Japan.

The KEI 3240 Computer System

is a highly reliable, marine type

approved system that is already in

use today. The main computer unit

is able to operate in temperaturesranging from 5°C to 55°C and

the local I/O units are able to

operate between 5°C to 70°C. This

robustness makes it ideal for ship-

borne applications.

Each rigid sail will be physically

raised, lowered and maneuvered

by a positional system which willFigure 1: Impression of the Aquarius MRE SystemTM on an Oil Tanker










































































































TECHNICAL ARTICLE

interface with the computer control

system. The rigid sails will be able

to move as an array or individually,

either automatically as directed by

the computer control system or via

manual commands entered by the

crew on the control console(s).

Most importantly, the positional

system will be able to store the rigid

sails in a protective housing so they

are not damaged during storms or

do not interfere with cargo loading/

unloading operations.

Another important feature of the

Aquarius MRE System™ is that it

incorporates an advanced energy

storage system based on Lithium

Ion technology from Corvus Energy

Ltd. of Vancouver, Canada.

Corvus Energy’s advanced lithium-

polymer battery technology will

store energy collected by the solar

panels or it can be used to store

power from the ship’s generators.

The batteries will then help power

the ship’s electrical equipment orbe utilized as a power source when

the ship is in harbor or at anchor.

Using power from the batteries will

also satisfy the growing demand

at ports to reduce greenhouse gas

(GHG) emissions and particulate

matter.

Additionally, the power stored in

the battery modules could be used

as a highly reliable back-up powersource.

Each AT6500 series battery module

from Corvus Energy has the ability

to be combined to form a custom

sized pack—from 6.5 kWh to

multi-megawatt applications. The

modules can be configured in any

number of ways to build the size

of the required battery pack, and

will allow for the energy storage

component of the Aquarius MRE

System™ to be highly flexible.

The AT6500 modules are alsoinherently safe and capable of

being used in the most demanding

environments as the modules and

the connectors are fully sealed.

Further important features of the

battery modules are that they are 99

percent recyclable, lightweight and

require no ongoing maintenance.

At this stage, there are plans to in-

corporate CIS solar module tech-nology into the Aquarius System™

because of its performance, plus it

also complies with European RoHS

(Restriction of Hazardous Substanc-

es) regulations. However, other

solar cell technologies are being

studied and may also be used.

On a large bulk ore carrier, the total

installed solar power could be 500

kWp or more. But as the cost of

solar panels decreases and their

efficiency increases, it may become

feasible to expand the capacity of

the installed solar power toward 1

MWp.

Future Developments

The large-scale use of modern re-

newable energy technology on

ships is still in its infancy. As various

technologies develop in the years

ahead, we are likely to see the adop-

tion of wind and solar power solu-

tions in a variety of forms become

widespread across the shipping

sector.

The control, energy storage and

power management systems for

these solutions are sometimes

overlooked, but will play a critical

role in terms of making renewable

energy a viable source of energy

on-board the ships of the future.

For more information about the various development projects at

Eco Marine Power (EMP), please

click here.

About the Author

Greg Atkinson is a technology

professional with over 25 years

experience that includes service

in the Royal Australian Navy and

holding a range of positions in the

telecommunications sector suchas network operations, network

support, project management

and product development. He

holds an MBA, a B.Sc in Electrical

Engineering, an Associate Diploma

in Electronic Systems Maintenance

and is a Member of the Australian

Institute of Company Directors.

(MAICD). Greg is currently based

in Fukuoka, Japan, where he is

leading various design projects atEco Marine Power.







































































































http://www.ecomarinepower.com/en/research

http://www.ecomarinepower.com/en/research

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