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None of these products are currently sold by OLPC

See Product News for product availability.

This is a space for presenting XO peripheral ideas in a concise manner for review by the OLPC core team. Feel free to expand the description of your idea on a linked page but please keep to the formatting on this page.

Alternatively you may talk to me here, but do check my userpage for other ways to contact me.

We now have a mailing list: peripherals AT


Below is a list of power product concepts for the XO. Please refer to Battery and power for an extensive discussion about many power related options.

Power diagram illustrating problems to be solved

Hand Crank

Desk fixable hand crank power generation device capable of generating 5-8W.


A Pull-Cord Generator achieving 20W peak average power. Simply hold the PCG in the palm of one hand, pull the cord with the other hand, and generate instant energy.

Solar Panel Options

XO Solar (May 2008?) Yamaplos 20:23, 19 April 2008 (EDT)

A 14V 5W 400mm x 280mm flexible solar panel.

Solar Blanket

A 50W 1.65m x 0.45m foldable solar blanket

Freeplay Weza (Foot Pedal)

A foot pedal power generation device capable of generating 40 Watts.

Wind Tower

An array of wind powered alternatives which show hope of generating power.


A technology capable of generating energy from aeroelastic flutter by using a taut, vibrating membrane, coupled with a no-contact, direct-drive electrical generator.

Micro/pico hydro

A range of ideas for implementing small-scale hydro power schemes suited to powering the XO for remote communities.

Bicycle Cassette

A bicycle attachment to generate power for the gang charger

Multi Battery Charger

A multi battery charging station to enable wire free use of XOs throughout the day.

XOctoPlug & CentiPower

8 in one anti-electrocution and tangle-free XO power supply to be used in the classroom to improve safety, convenience and battery life.

Modular Power

An electrical generation solution with customisable gearing and electronics that can be used with different locally designed and built mechanical systems.

Energy Storage

Electrical Energy is often unreliable or unavailable in many developing countries. This makes storage of energy when it is available very important. New environmentally friendly, efficient and safe methods need to be developed.

School Server UPS

A UPS designed to work with the school server with 12V and mains inputs, and capable of a 30W output for 24hours at 12V, therefore 720Wh of battery capacity.

Body Fluid Power

Electric power using liquid as a catalyst can be produced with a special mixture of magnesium and carbon. Could liquids including beer, apple juice, cola, saliva and of course urine be used to run the XO?

Zinc-Air Fuel Cells

Zinc-air fuel cells work by extracting oxygen from the atmosphere which reacts with zinc metal fuel and produces electricity. With Zinc being one of the most abundant elements on Earth this could be a great solution for the laptops.

Getting the Most Out of Your Solar Panels

The following are questions an answers from Richard Smith OLPC Solar specialist, and questions from participants in April 4th Sunday Forum.
Sunday April 4th Presentation
RE: Solar Input and managing charge levels for XO-1 and XO-1.5 Discussion with guests Richard Smith and Robert Pilawa. When using solar panels to charge XOs, the output of the panel varies according to the amount and intensity of the sun. This means that sometimes the voltage spikes up and even exceeds the limit of the XO controller, and can trigger a shutdown of the charge.
The guest specialists discussed the design of the XO input circuit, and a new device under development by Robert Pilawa that can control the input voltage cheaply.
Solar Presentation Agenda from Apr 4:
Robert Pilawa's Slides:
Pilawa-Podgurski, MIT Mathematics department
Robert Pilawa & Brooke Pilawa-Podgurski, MIT grad students, Cambridge, Massachusetts/MA, USA]' to 'Low cost solar charger for the developing world: low cost solar charger with built-in power tracker, adheres to USB charging standards, can charge most cell phones, portable lights, lead-acid batteries. . It can produce up to 35Watts in full sunlight.

Problem: Hot sun issues in Kenya etc creating unexpected conditions. Everything charges fine and then things mysteriously stop.
Richard Smith Richard went back to manufacturer (GoldPeak) to clamp voltage at ~18V to prevent this problem. Using a small circuit added to the solar panel.Samples of this solar panel were built.Testers all said it worked great. But then Richard himself tested it and discovered another small problem with even this new solar panel.This should now be corrected (this $2 added circuit helps) and is now going into production.
XO Power Design
Charging chip is the entire power source of the laptop. 1 input chip creates power rails for all devices on motherboard. Separate power supplies for each of those devices.

RS: XO 1.5 Changes to Support Solar Charging
XO-1.5 overvoltage at 25V instead of 18V for XO-1.XO-1.5 can limit the power it draws.
If you want to set the XO-1.5 to use no more than 10W, you can use battery as buffer.

Allows you to use panel at more optimum range.(Power draw of XO above 10W!) XO-1 sucks up to 17W; XO1.5 sucks up to 20-25W)

Control duty cycle of charging chip "turning it off for x-amount of time"
  • EG. Turn it off 50% of time.. you get 12.5W
  • EG. Turn it off 0% of time.. you get 25W
  • How does the user in the field accomplish the change?
  • Power rail 7.5 - 8V

Question? what is oscillation and is there a fix? Answer: Richard Smith: you'll hear a "screaming" noise Output voltage of panel drops / rises / drops.

Q? There has been talk about oscillation issues at low input voltage/power. have these been fixed already? A: 1-2 kHz range is in audible range.Inductors / capacitors.On XO-1.5 it's MUCH louder. Running change Richard will be ordering to production. Richard has attempted to make on power-limit implementation in field automatic. Is this change firmware-only or an ECO? Both.. (must be XO-1.5)

Q? Is oscillationfix HW? A: Richard: yes Easy modif.. resistor changes.Tiny resistors, beyond normal soldering.Microscope required..All that's coming down the pike..
Other ways of Charging
  • standalone charger.
  • Problem: MBC (multi-battery charger) too expensive.
  • MOQ (Min Order Quantity) too high, perhaps 1000 units.
  • New concept: single battery charger?
'Q:?' How about a kit for do-it-yourselfers at a much smaller cost? 'A:' "Leave a Little Room" in Ethiopia / Tanzania requesting 200.NS How about always ordering 2 batteries per laptop? Richard: yes!Mulitple Battery Chargers was about removing wires from the classroom..But now a different driving requirement?Workflows already set up so MBC hasn't caught on so far.Several deployments build their own charging racks..

Locked down sometimes for security.But we try to encourage kids to take XOs home. So 2 batteries would make sense. Nancie: Roger in Thailand discussed battery failures "due to improper shutdown" ?

Purchasing More Batteries:
Note: A Battery size changed in XO-1 version, but all batteries work? $25 batteries available at [1]. $28 panels avail now for iLoveMyXO to buy (100 MOQ)
Robert Pilawa’s Low-cost solar controller and why!
1. charge controller basics
2. max power point tracking
3. cost
4. prototype
Note: Batteries commonly damaged in the developing world, because people buy the cheapest etc. Overvoltage protection critical.Similarly at night, if you charge the battery dry (too low voltage) you will trash your battery, sometimes if you do this even twice.
Q? MPPT in charge controller?? A: Is it only for XO-1 because xo-1.5 has it built-in? or has doing it in the charge controller some advantage for xo-1.5 as well?
'A:' 12V panel has an open circuit voltage of 23-27V? but MPPT of 17V? Think of it as gear box, of car of bike. If you don't have gearbox, you can't get up to 55MPH.So you will be running in 1st gear, and wasting your power. You need DC-DC power converter.. staying at Maximum Power Point (MPP).MPP depends on the temperature and sun. You end up wasting up to 30% of avail power of panel. Solar panel manufacturers keep pressing price down and down.Same with lead-acid batteries.You can take advantage in the developing world.Price pressure coming from household uses.Developing countries can take advantage.But now fancy electronics in the middle hasn't yet had these economies of scale yet.Needs to happen.
  • Targetting $0.25 / Watt?
  • Low-cost Maximum Power Point Tracker.
  • Target: 100W tracker $25
  • In the US a household version today can be $20.
  • Low cost power electronics help..
  • High-volume parts..
  • New Target Application: XO / off-grid applications..
  • Innovative encapsulation techniques (for Robustness)To recharge lead-acid (car) and cellphone batteries.Put it in between your solar panel & XO.Get the real 10W instead of 7W.As Richard was alluding to.Do this on the XO itself would be nice, sure, but we need external circuity in real world here.Many XO installation?Let's say you have 10 of these old Peak Panels.Daytime charge a lead-acid car/marine battery.Then at night charge the XO's / batteries from the lead acid battery.
Q? Cost consideration?
'A: SJ: typically you can capture maybe 30% or more of avail power not used if you have a low power panel... with less than a 50W panel it wouldn't make economic sense, if you can get a 20% increase in power but could just buy another panel for $4/W. (you'd probably pay $6/W for a panel for consumer work) 20% extra power should be used. This makes sense if the additional cost of the fancy controller is less than $0.80/W, otherwise you'd just buy more panels.
'A:' Robert Pilawa : Current Technology and Costs: Todays' designs areabout $1/W commercially. We are targeting something like $0.25/W. this should be available for testing early summer. We'd love to get people with solar installations to have general field testing on what is important feedback.
Q?Why does cost scale with power? 'A:' Robert Pilawa: panels' costs scale with power.Imagine 20% surplus power coming from 10W converter (eg. 12W). From an installation perspective you should look at it as $'s per Watt. Today's designs cost $1 / Watt
'Q?'SJ :should folks use small panels or large panels.Blankets of panels? EG. 500 square feet of panels? 'Q? ' What if big client arrives? "A:'SJ: rule of thumb too simple 10W panel or 1000W panels very different. Metric we should use $/Watt..
'A:' Robert: that's a market analysis, yes
'A:' Nancie: on Vietnam, she had written primer on designing solar/battery setup.

What if teachers may grab power for fan & other uses
'A:' Robert: extra fans!Richard: there's never extra power!
'A:'Nancie: adults' cellphones will be charged. there will be issues. cellphones are 1/15th the power perhaps, on the bright side.(1/15th the power of XOs?)
'A:'Nancie: power diagrams on the above page [[2]]
Q? what are most people using in the field?
'Answers:'Richard: 10W olpc recmomended panels. Goldpeak will make... other wattages. We have a 10W b/c its a nice number, they will make panels for you in whatever size. The Solomons will use 15W panels because that's a primary vehicle for them... and the extra 5W makes a diff.
Why and how Regulators or Controllers?
'A:' lot of people try to use these other panels, but: the goldpeak panels is suited... the low-peak voltage is lower than most other panels and most others out there trip the voltage limit quickly(which keeps them from charging an XO) Others with a more advanced voltage regulators are (comparatively) expensive.
'A:' If you have a battery in the system, lead acid or otherwise, you absolutely need a controller. You can think of the XO as being a battery in the system; its controller is on-board inside the XO.
Q? How to manage or view the solar input levels?
'A:'Is the application at the panel, or b/t the building and the charge controller? Where is the controller / device? 'A:' the limiter is a stopgap; this would make it(charge controller) you'd save a small amount with the limiter Richard: this is much better than limiter (charge controller) which will no longer be neccesary.
Q: What is the Cost? A: (maybe $2)
I should say that I hope to be able to get robert's design implemented as an option you can purchase with the panels.then you could order an olpc solar panel and have the circuit built in.
Q: How long does it take to charge an xo from a Solar source?
'A:' 30W hours with a limiter or what have you?
'A:'Empty to full, with a 10W panel, that's 3 hours. That is max uninterrupted output in reality it's somewhat longer, seldom do you get peak output unless you are in a sunny tropical area.the 10W panel also. It's not that 10W is a limit.
Q: How do you evaluate the required input for charging?
'A:' If you're in Kenya, you can get strong sun and more than 10W output. That's why you use the W-hr number to estimate time to charge.
Q:You're saying robert's device will help that?
'A:'no, if the device is doing max power output it won't

help.'A:' robert: right now you'd pull voltage out at 11 or 12V, right? 'A:' richard: yes, but then the XO gets real hot and it averages out...

Q:How can people visualize how efficient their panels are being?
'A:' Suggestion: the charge-controller could have a display.richard: you could put something on the working on learning activities to do that. Comment: that would be specially good on the 1.5 where you can get realtime data from the ec.
'A:'Richard: you could get a good running average on the 1.0 (in real time)

Q?: in consumer's tech what are people getting for 'that extra $5' if that's what this controller would cost?

'A:'richard: superior, stable performance in low-light conditions; and would be able to charge devices they wouldn't noramlly be able to (at different voltages:cell phones, lead-acid batteries, etc; (there are additional smarts in there)

Q?: Suggestion Learning Activity NS: As you think about an activity to monitor power coming in, it would be useful to monitor / log each week over the course of the year the gradient, so they know what to expect the following year. SJ suggestion - and also let them record the angle at which they support the panels for optimal charging!

'A:' Activity could include info on the course of the sun around the earth at different lat/longs.(related to the optimal angle, over the course of the day, for each day of the year) and then you can include data on the physics of solar panels what their output is related to solar illumination. How power output changes with a sunnier day, a cloudy day with mirrors reflecting sun onto the panel from many places (embedding each panel in a parabolic mirror?)

Q? What about controlling from a interface

'A:' on the xo-1 it is v easy to understand such things; log data is already supported in the file system. OLPC PowerLog records this information. On the 1.5 and new f11 for XO builds
Discussion on Solar intensity and Solar Panel Optimal use
COMMENT: I have heard from people in Peru that elevation (like in the

Andes) interferes with solar panels. Doesn't seem logical. Is it true?

Q? Some people have said that elevation make solar panels work more poorly
'A:that didn't make sense to me: ' no, it works better at elevation earlier.'A:' if you keep adding solar power, you can get more and more power out of a panel until it burns out.
Q?what data sheets can we get about how the panels work? their max/min power output at different input illuminance, standard deviations,etc.
'A:' They are all on the wiki and Serendipity at

Free Charge Controller project: open-source maximum power point tracking (MPPT) for solar panel, wind turbine, etc.


This is an area to describe connectivity related peripherals

This page describes number of different networking scenarios.

Power diagram illustrating problems to be solved

Active Antenna

A device to extend the wireless mesh range of the XO. This is an external USB wireless unit with superior aerial design. It can also work independently of the XO when supplied power.

XO Modem

A selection of methods to connect an XO to the internet.

Solar Repeater

A standalone unit which increases the range of the wireless mesh, powered by solar energy.

Optical Data Link

This $100 device has 1.4km range and has a stable 10Mbps full duplex data rate. Ronja is an optoelectronic device you can mount on your house and connect your PC, home or office network with other networks

Satellite Broadcasting

One-way delivery of digital information via satellite

xMax Communication

Capable of extending the range and reducing the transmit power compared to conventional approaches, including cellular technologies and fixed wireless approaches such as [ WiMAX

WiMAX Communication

WiMAX (Worldwide Interoperability for Microwave Access) is a telecommunications technology aimed at providing wireless data over long distances in a variety of ways.

Wireless Modem

A plug in device that connects the XO to the internet in locations where a wireless access point is not available. This could be achieve by using an existing mobile phone and data cable, or by developing an extremely low cost mobile phone/modem for the XO.

USB Ethernet Adaptors

A USB Ethernet adaptor enabling reliable wired connection of the XO.

AM/FM Radio Transmitter

A low power school/community based radio transition service broadcasting recorded audio blogs of various content posted by XO users.

AM/FM Radio Receiver

A plug in AM/FM radio receiver (MIC IN or USB) would enable children/families in remote areas to continue to receive information from services such as BBC world service when outside of mesh range.

AM/FM/SW/LW Radio Receiver

A USB plug in AM/FM/SW/LW radio receiver to enable use of services such as BBC world service when outside of mesh range.


USB Journal

To enable multiple users on the XO it would be helpful to have a USB key that plugged into the XO which stored all personal data (specifically the Journal). Make the USB dongle a bright XO green to avoid loss. Will also attract kids to journal. Possibly add a LCD to view files on dongle when not plugged into XO or server.

Sensors & Measurement

Sensors for MicIn

A variety of sensors that can plug into the MicIn port on the XO. These sensors can also be used with the MicIn Amplifier USB Amplifier to enhance their sample rate and usable range.


With a range of sensors being created for the MicIn port this USB device would give enhanced sample rate and voltage range enabling higher measurement accuracy.

USB/MicIn Scale

A hard wearing scale that can sit on a desk, hang from a tree or be used to plot force/time graphs on the XO screen.

USB Oscilloscope

A dedicated USB oscilloscope probe for advanced users.

TeleHealth Module

A collection of essential medical diagnostic and treatment tools.

Science Kit

A kit of parts designed to aid the teaching of basic scientific principles. Including magnets, light sources, prisms, conductors, isolators and various circuit components.

USB GPS Receiver

A low cost GPS chip with antenna oriented with the OLPC's design in mind. Perhaps adjustable for use in OLPC's open or closed configuration. For geographical projects and OpenStreetMap contribution.

Input Devices

MIDI Instruments

Complementary to the music software packages on the XO a collection of MIDI instruments could expand both the interest and usability of the programs.

Buy cheap software online legal


External Tablet

A large external touch, drawing and writing pad enabling easier drawing and mathematical formula input.

Touch Screen Overlay

A screen attachable touch sensitive layer enabling data input through the XO screen when in tablet configuration.

Game Controller

As more software is developed for the XO a dedicated games controller may become desirable by some users.

My Lil' Mouse Child Friendly Mouse

A specially designed child friendly mouse which solves dexterity issues some young children face when interacting with touch pads or standard mice.

Available at:


A USB scanner which can be rolled over different mediums and surfaces to acquire the image. See similar consumer model. Possibly wireless charging. Bright XO green to attract kids.

Camera Accessories

A selection of lenses and mirrors which can transform the XO camera into a microscope, telescope and a periscope.

Mini Camera

The XO camera is becoming one of the most used functions of the XO. Possibly a separate slim line camera would be a great addition to the package.

Magic Wand

A pointing instrument that can sense hand movements giving the user the able to control musical tempo and pitch in TamTam, allow painting, drawing or writing characters in air, or facilitate game play.

Output Devices


Possibly a standard printer which uses paper, but alternatively a printer which can print onto locally available medium. Or possibly a etch-a-sketch/Magna Doodle surface for continuous reuse.

Network Hub

A USB hub that connects wirelessly to the XO mesh network enabling the use of network printers and other devices.


A wireless projector powered by 2 XO batteries with a 2 hour run time costing $100. Or an add on kit for the XO screen.

USB to VGA / Video

An adapter which can be plugged into the XOs USB port and connect to a projector, display screen or television set.

Classroom Video Receiver

A wireless module that connects to numerous display technologies enabling classroom presentations using the XO.


Children have started to use the laptops as musical instruments and want them to be louder.

Miscellaneous Peripherals

This section should be used to describe peripherals that don't fit into any other categories or are unlikely to be appropriate for OLPC for some time.

Bug Labs

Bugs is an innovative new hardware and software platform enabling users to create unique and personalised hardware running customised software to do, well, anything you want.

Protective Case

An entirely water proof protective case for the XO capable of protecting it from even the most severe environmental conditions.

School Server

The school server extends the storage and computation provided by each the XO laptop, as well as providing a local library and a mesh portal to the Internet.


A two-way satellite ground station with a dish antenna mounted onto a van incorporating wireless mesh access points. This could allow extremely rural areas to have periodic internet access at a low cost.


The idea is to connect simple and small robots to the XO. The little robots could be made from recyclable materials, and should be connected to an activity to manage them.

Manufacturing tools

  • We should design a low-cost, easy to manufacture NC (Numerical Control) tool system. It would consist of a multi-axis robot arm with replaceable inserts (drills, grinders, and others), controlled by NC programs on an XO. This tool could be used to make further tools of considerable complexity.
  • Minilathes aka Industrial Revolution in a Box. Not a directly connected peripheral, but useful for making them. There is a path from here to a full set of machine tools for making production equipment of many kinds, including the NC system described above, along with the full range of hand and machine tools, molds, and dies for small-scale production systems.
  • There are 3D "printers" normally used for creating prototypes. They use inkjet printer technology, but spray drops of fast-setting plastic. Molds can be made from these prototypes for casting plastic, metal, and glass products.

Peripherals People

Below is a list of collaborators working on peripherals concepts.

  • Arjun Sarwal
    • arjun(at)laptop(dot)org
    • arjs on irc
    • Wrote the Measure activity while interning for OLPC last summer
  • Joshua Seal
    • josh(at)laptop(dot)org
    • Currently managing the peripherals page and developing a number of peripherals
  • Zdenek Broz
    • dicts(at)centrum(dot)cz
    • Has group of developers at Brno University of Technology(Czech Republic) working on a USB microcontroller/ADC platform
  • Honza(Jan) Kovar
    • Is lead developer and programmer at Brno University of Technology(Czech Republic)
    • Working on a USB microcontroller/ADC platform based on the SilLabs C8051F321 chip
  • Ian Daniher
    • it.daniher(at)gmail(dot)com
    • Currently focusing on the TeleHealth Module
    • DyDisMe on
  • Bernardo Innocenti
    • _bernie or _bernie|home on
    • Has experience programming Atmel Chips(ARM/AVR), Motorola, Intel, PPC, Texas Instruments...
  • Rafael Ortiz
    • dirakx or dirak1 on
    • wrote most of EKG page
    • has a prototype for the EKG.
    • Interested on developing hardware and software related to peripherals.
  • Mary Lou Jepsen
    • mlj at laptop dot org
    • is working on video microscope, periscope, solar, $100 projector and other things
  • Rowen Remis R. Iral
    • User:Wenmi01 wenmi on
    • OLPCPH Project management
  • Steven Burns
    • steveb1492(at)gmail(dot)com
    • TeleHealth Module-Health Library
  • Aaron Kaplan
    • aaron(at) irc: aroscha
    • working on another mesh range extender
  • Duane King
    • dking([at])
    • User:Dking
    • Embedded/Security SDET Interested in Power Generation and Blind Accessibility for the OLPC XO.
  • Matt York
    • myork at
    • Working at "One Media Player per Teacher" ( is researching and testing external speakers and battery charging solutions
  • Mel Chua
    • irc:mchua
    • electrical engineer w/ embedded & USB experience; accessibility peripherals (primarily auditory - Mel is hearing impaired). Beginning to assist Ian with TeleHealth Module, working at full-time OLPC Chicago office this summer which will be doing peripheral development (likely a bicycle charger, among others), documentation.
  • Jono Nevile
    • Biomedical Engineer keen to work on TeleHealth Module
  • Ixo X Oxl
    • irc:iXo
    • IT Consultant 20+yrs, eWaste/electronics REuse/REcycling 30+yrs, Technology generalist, Implementation/Education of centralized information resources and delivery.
  •  :Tinktron
    • Retired USAF NCO 20+yrs electronics, computers
    • 2yr Electrical Engineering Technology degree
    • Renewable energy sources, tech education, science education
  • Your Name Here
    • email or irc alias
    • skill set or such

See also