Tuesdays, 9:00AM-11:55AM

Go to: Main class page goto week: 01 02 03 04 | 05 06 07 | 08 09 10 | 11 12

Schedule Overview:

Date	Class	Date	Class
1/23	1. Intro, start kinetic projects	3/13	Spring break, no class!
1/30	2. Generate I: Kinetic	3/20	8. Solar II:BOS, Solar project report
2/6	3. Storage I: Capacitors	3/27	9. Kinetic II:Big Kinetic
2/13	4. Kinetic presentations, start solar projects	4/3	10. Final workshop
2/20	5. Generate II: Solar	4/10	11. Special topics
2/27	6. Storage II: Batteries	4/17	12 Final Presentations
3/7	7. Solar hardware demo, low power lab, start final

Student Documentation:

Your documentation links will go here.

Roland Arnoldt
Yeseul Song
Sam Chasan
Jason Young
Dan Oved 
Dominick Chang
Jenny Lim
Anita Mbabazi
Fanni Fazakas
Marcha M Johnson
Arnav Wagh
Daniel Castano

Some previous class work:

Notes: Dorothy and Chetan’s Air Quality Balloon, Rios’ Ironman and Pedal Synth, Mithru’s Screaming Sun, Easter Vogel, Mathrua’s 64-LED 4-generator car, class shot, Synthenetic, class shot, Circuit Board, Enertiv Hardware, SolaSystem, Heely generators, Light Swing, Solar Xylophone and some of Rory’s other stuff, Our little 721 Broadway panel, Daft Junk, Kina’s Songlogger, Joao’s Sol, Oryan and Edson’s Solar Power Man, Hugo and Joe’s Datalogger, Natalia and Jacob’s light bug, Pawnetic Playground, Turntable, Enertiv Software, Jesse’s Sound Level Sign.

Week 1: Introductions

1/23/18

Most of your projects at ITP have an on button and a power supply – they are active energy users. They might even never turn off. This is possible because computation has become extremely efficient, abundant, and cheap. At the same time, the work you create at ITP may help make technology more compelling and irresistible part of daily life. The energy consequences of that on button are magnified.

But if you’ve ever smelled that “hot electronics” smell from a frying transistor or voltage regulator, you’re closer than most to being able to tackling questions about energy directly. And because of your work at ITP, you are in a good position to understand energy in a precise and nuanced way – an understanding generally all too lacking.

In this first class we begin the adventure of looking at the world – from the scale of an individual electronics project to the scale of the universe – in terms of energy. We introduce (or reintroduce) some of the few terms and units we will rely on throughout the semester: watts, joules, work, power.

The first class serves as an introduction to some of the larger themes we will pursue over the course of the semester. We look at the origins of the course and the relevant parts of my background, and hear from you about your experience and expectations.

More energy projects:

A shoe generator patent image from 1923 — A shoe generator from 1923

Photos: Soccket (See PM story from 2010 and updated in 2011, and this public radio report from 2014), Gravity Light, Mine Kafon, Solar Sinter. Others are kinetic energy patents through the ages – filename = patent number.

In class:

Introductions
2003 blackout presentation. Video retrospective of the event.
Form teams for the kinetic challenge.
Build and measure pendulums.
If time allows, begin Kinetic Slides (to be continued next week).

Reading:

An excerpt from Vaclav Smil’s earlier work: Energies: An Illustrated Guide to the Biosphere and Civilization. 1999, MIT Press, online here [pdf, 2.2mb]
Subscribe to The Energy Gang podcast and listen to the most recent episode.

Assignments:

Find one or more potential “converter” candidates for the Kinetic challenge. DC gear motors work very well. Steppers, or (to a much-lesser extent) piezo crystals are potential candidates. Also find light sources – hi bright LEDs, etc. Can you get your converter to light up your light? Diodes and capacitors will also be useful in the coming weeks. Bring all materials to class next week, and brainstorm solutions for the challenge with your partners.
Watch the section of this video (from 22:25 to 30:30) that introduces conservation of energy.

Housekeeping:

Get the Smil text.
Send me the link to where you will be keeping your documentation. Remember – your link should take me just to stuff for this class.
Sign up for a shop safety session if you did not take one last semester. Follow all shop policies.

Week 2: Generate 1 – Kinetic Energy and Conditioning

1/30/18
We’ll quantify kinetic energy, and see how it is converted into electricity (accounting for almost all of the world’s electricity generation).

Last week we used some basic physics like force = mass * acceleration to start to understand our SI units for energy (the joule = 1 newton * 1 meter) and power (1 watt = 1 joule / 1 second). We used this to calculate things like the difference in gravitational potential energy in the masses of our pendulums when they were raised to their starting points.

This week we’ll start with a very birds-eye view of energy, covering the history of the universe in a few minutes, up to “the world until yesterday”. We’ll see the genesis of heat engines – devices that turn chemical energy from fuel into useful mechanical work and which have fundamentally shaped the modern world; and we’ll introduce induction, the primary means by which we turn mechanical work into electricity. Almost every electron we use is pushed to us this way.

In class:

Lab: Generating and Conditioning. Topics will include:
- Measuring current with a meter
- Measuring open circuit voltage, closed circuit current of a converter
- Intro to: Voltage regulators, bridge rectifiers, role of capacitors
Kinetic Energy 2018 (pdf).
5 Minute Energy 2018 – The big bang through the industrial revolution. (here’s the latest Lawrence Livermore flowchart for the US energy sector)
Kinetic Electrical one-sheet, updated electricity source data here, note diminishing role of coal.

Notes: Columbia is having an Energy Symposium this week. Student price is $35.

For reference:

This video shows a Soccket being assembled. The motor/generator appears to be a Precision Microdrive DC motor such as this one from Sparkfun. The battery is probably a single 18650 lithium cell. This is the Soccket patent. Aside from the generator and battery, the main other component is the LTC34105 chip from Linear Technology.
There’s a set of iFixit guides to the Gravity Light, which let us see the insides of an early version. Here’s their patent. Note they eliminate nearly all the circuitry save the motor/generator and LED, relying on the mechanism to store and release energy. Precision Microdrives appears again, this time as a consultant to the Gravity Light team for their gear train.
The ingenuity of these types of things lies in the mechanics more than the electronics. The magnet/coil side of things is pretty settled. Note this 1900 patent for generating electricity from the wind; elaborate mechanism of sails, pulleys, and chains, ultimately spinning coils inside a (horseshoe) magnet.
As such, the same ideas resurface continually. Note all the shoe power patents above. Also, here’s three versions of a revolving door generator, including the “world’s first” in 2008 and one from the 1920s.
We’ll probably see something like this in class (this is last year’s):
This cool reconfigurable gearbox and motor kit shows how gearboxes trade speed for torque.

Reading:

Smil, Energy, a Beginner’s Guide Chapters 1 and 2
Energy Scavenging for Mobile and Wireless Electronics, Paradiso, Starner, 2005.
Some good material on induction can be found in this recent Make project

Assignment

Continue building your kinetic device. Using an oscilloscope and multimeter, measure or estimate the open circuit voltage and short circuit of your generator. How fast can you charge a capacitor?

Week 3: Storage 1 – Capacitors

02/6/18
We’ll look at the connection between motion and electricity via induction, and quantify the energy stored when charging capacitors.

An LED is a pretty forgiving load to power, since it doesn’t doesn’t need to boot up and compute anything. As long as we provide enough current (but not too much) we can light it up. So using an LED (or rather, light in general) for the kinetic challenge is a good place to start. However, we might eventually want to power a less forgiving load – something like a microcontroller that requires a more carefully regulated power supply.

The Paradiso/Starner reading gives a good introduction to the kinds of sources that might be considered for powering mobile electronics. (BTW – they’ve treated each topic covered in that paper in more depth elsewhere. Search for their papers if a particular area is of interest.) Typically those sources are low power and intermittent, both factors in requiring some degree of energy storage.

In class today we’ll look at adding capacitors to the rectifier circuit we saw last week, and we’ll calculate the energy stored in a capacitor. Once we know that we can determine the “real world” power a generator is capable of by using it to charge a capacitor: the energy added to the capacitor, divided by the time to do it, yields the power of our generator.

In class

Discuss GTM, Paradiso and Smil
Energy Storage, Capacitors, Strategies for conditioning kinetic input.
See kinetic challenge hardware in progress
Lab: Estimating power by charging capacitors

Reading:

Smil – chapter 3.
Biomechanical Energy Harvesting, Donelan et. al.

Watch: Inductor video for more information on step up converters and using steppers as inputs

Assignment: Finish kinetic challenge for presentation next class. Be prepared to quantify your work using energy and power terms.

Week 4: Kinetic presentations

2/13/18
You will present your creations for the kinetic challenge in class. Some projects from previous years:

Kinetic Presentations

Theme for the day:

In class:

Solar challenge kickoff
- Form teams
- See microcontroller load measurements
ITPower discussion with Mathura Govindarajan and current student Jenny Lim. Here’s the Enertiv energy monitoring system

Reading:

Smil – chapter 4.
This short article on Tesla’s large grid-attached battery.

Assignment: Choose your “computation” for the solar project. Create a rough energy budget based on experience, direct measurement or estimates from documentation – post this your blog. If necessary, choose and order a battery, along with any other components you need.

Week 5: Generate 2 – Solar

02/20/18

We’ll take a first look at photovoltaics – a non-induction means of generating electricity.

Aside from nuclear, tidal, and geothermal energy, all energy ultimately comes from our sun. In space, near earth, this power flow is about 1370W per square meter; on earth with the sun directly overhead we can expect about 1000W per square meter. This enormous power flow drives the wind and waves (the kinetic energy of which we can capture), lifts the water that rains down and fills damn reservoirs (the elevation of which provides gravitational potential energy), and, for billions of years, has been captured by life on earth, subsumed by geological forces and transmuted into the fossil fuels – coal, oil, natural gas – that are currently powering our civilization.

But as powerful and pervasive as sunlight is, compared to the fossil fuels we’ve become accustomed to, it is diffuse and intermittent: it will take a lot of PV material, and the ability to economically store the electricity it produces, to run big parts of civilization. In this class, we start small, looking at BEAM robots and portable devices; these will serve as a basis for considering big solar power.

Assignment:

Continue working on Solar assignment. Have or have ordered all parts necessary to complete assignment by the end of this week.

Reading:

Smil – Chapter 5.

Resources:

Voltaic’s Blog – many great examples of small- to mid-sized solar (~10W – ~100W) with tutorials and DIY instructions.
Sparkfun’s guide to reducing Arduino power consumption
Another guide, using the Arduino Pro Mini.
Adafruit’s guide to measuring power use in microcontrollers, and estimating battery run times
Adafruit’s battery guide.

Recent presentations. Note – these aren’t edited to work as stand-alone resources. They are meant to accompany in-person lectures or videos.

18TW volume 1 (in class lecture)
Energy Conditioning Strategies (related video lecture here on ITP Energy channel)
Energy Storage (related video lecture on ITP Energy channel TK)

Week 6: Storage 2 – Batteries

02/27/18

We’ll consider batteries.

I’ve visited Thomas Edison’s factory in East Orange, NJ, now a national park. On display are Edison’s library, large and precision machine shops, his early recording studio (where a variety of cones performed the function of microphones) and a reproduction of “Black Maria”, the house-like film stage with a retractable roof that could be rotated to follow the sun.

Edison developed a robust nickel-iron battery used in early electric transportation applications. Many of his other devices, such as the cylinder recorder shown below, were powered by batteries in beautiful glass jars. Improvements in batteries since this time have been incremental – while the power density of batteries has increased (the ability to rapidly charge and discharge), their overall energy storage per unit of mass or volume has increased less rapidly.

In 2015 I wrote: “Some battery news this year (will any be around next year?) Sakti3, kAir (see also here), and packing peanuts.” As of this year, Sakti merged with Dyson, kAir pivoted and might have vanished, and there’s been no news since then on packing peanuts as batteries. This is typical of the battery space: each year brings promises of a new technology that will revolutionize batteries, but actual innovations that can make it to market and actually be manufactured at scale are few and far between.

Guest: Chris Neidl of Brooklyn Solar Works and previously Solar 1.

Presentation: