Schedule

Schedule

Tuesday, September 16

1410921000 Padre's Corner

Wednesday, September 17

1410967800 FLOSS Weekly
1410973200 Tech News Today
1410976800 Windows Weekly
1410984000 This Week in Google
1410994800 Tech News 2Night
1410996600 redditUP
1411002000 Ham Nation

Thursday, September 18

1411059600 Tech News Today
1411063200 Know How...
1411066800 The Social Hour
1411072200 Coding 101
1411075800 Home Theater Geeks
1411081200 Tech News 2Night
1411083000 The Giz Wiz
1411092000 OMGcraft

Friday, September 19

1411146000 Tech News Today
1411149600 This Week in Law
1411156800 Android App Arena
1411167600 Tech News 2Night

Saturday, September 20

1411236000 The Tech Guy

Sunday, September 21

1411322400 The Tech Guy
1411336800 This Week in Tech

Monday, September 22

1411405200 Tech News Today
1411408800 Triangulation
1411414200 iPad Today
1411426800 Tech News 2Night
1411428600 Marketing Mavericks

Tuesday, September 23

1411491600 Tech News Today
1411495200 MacBreak Weekly
1411502400 Security Now
1411509600 Before You Buy
1411513200 Tech News 2Night
1411516800 All About Android
1411525800 Padre's Corner

Wednesday, September 24

1411572600 FLOSS Weekly
1411578000 Tech News Today
1411581600 Windows Weekly
1411588800 This Week in Google
1411599600 Tech News 2Night
1411601400 redditUP
1411606800 Ham Nation

Thursday, September 25

1411664400 Tech News Today
1411668000 Know How...
1411671600 The Social Hour
1411677000 Coding 101
1411680600 Home Theater Geeks
1411686000 Tech News 2Night
1411687800 The Giz Wiz
1411696800 OMGcraft

Friday, September 26

1411750800 Tech News Today
1411754400 This Week in Law
1411761600 Android App Arena
1411772400 Tech News 2Night

Most Recent Episodes

Security Now
Episode #473: Google vs. SHA-1 September 16th, 2014

Steve Gibson analyzes Google on deprecating SHA-1.

Tech News 2Night

iPhone 6 NFC for Apple Pay only.

MacBreak Weekly
Episode #420: Apple Hangover September 16th, 2014

Insight into Tim Cook

OMGcraft

Chad shows how to make armor stands and everything you can do with them in Minecraft 1.8.

Tech News Today

Samsung marketing hits a new level with the upcoming launch of its YouTube sitcom.

Marketing Mavericks
Episode #23: One More Thing September 15th, 2014

Apple's special event, T-Mobile's CEO, and the NFL.

This Week in Enterprise Tech
Episode #107: Microsoft VDI September 15th, 2014

All about VDI

iPad Today

Yahoo News Digest, Biocolor, Padcaster iPad rig

Tech News 2Night

FBI Finalizes Facial Recognition System

Triangulation
Episode #167: Dr. Lawrence Krauss September 15th, 2014

Director of the Origins Project

Know How... 91

F1 Turbo, Solar Powered Rasp Pi, and Goat Sim Tips

May 1 2014

Mercedes is wining F1 with a new twist on an old technology, power your Raspberry Pi with the sun, and Goat Simulator Tips.

Solar 101: Solar-Powered Pi

Materials:
Solar Panels
Charge Controller
Battery
12v to 5v (USB Charger)

Tools:
Wire Snips
Wire Strippers
Screwdrivers
Multimeter

Steps:
1. Determine the Draw of your Device(s)
2. Size your Battery
3. Calculate your Solar Panel Needs
4. Choose your Controller
5. Wire it!

The Draw of your Devices:
* If you're building for a house, you can look at your electricity bill for the past 12 months. That gives you a good indication of your total usage as well as your high and low usage months.
* For medium-applications, a Kill-O-Watt works well, but it has a large margin for error, especially when dealing with smaller devices
* If you're building for a small device, check the specs of the device(s) you want to power.
- A spec sheet is a good place to start
- Remember that you must also account for the inefficiency of any charging unit

A Raspberry Pie pulls 700 mA of current at 5 volts at maximum power. (It pulls 300mA at idle)

Watts = Volts * Amps
- W=VA
- West Virginia

That means the RasPi draws 700mA at 5volts, or 3.5 Watt/Hours at maximum load.
** We need to supply the RasPi with 84 Watt/Hours of power per day.

Size your Battery
You need a battery that will support your application.
* Your typically want a battery that can support your device(s) for an acceptable amount of time, assuming that there will be days when your solar panels are completely ineffective.
* For an application like the Raspberry Pi, since it doesn't draw that much, I wanted to design a system that could go 2 days without ANY solar power input.
- Since the daily draw of a RasPi is a maximum of 84 Watt/Hours a day, I need at least 168 Watt/Hours of storage.
* Most small-application solar charge regulators work at 12 or 24 volts. I chose 2 x 12v 8Ah battery that will give me 192 Watt/Hours of storage

Make SURE to get a deep-cycle battery. If you don't you'll quickly find that your batteries don't provide their rated power because of the memory effect. (Most batteries are NOT designed to run all the way down.

Calculate your Solar Panel Needs:
You need to know (1. Draw of your devices) and (2. PEAK Hours in your Location)

Peak Sun Hours is the equivalent number of hours per day when solar irradiance averages 1,000watts per square meter.
- You want to know the amount of sun energy you'll receive per day on the WORST MONTHS of the year.
- Included is a "worst case scenario" solar map based on data from the past 30 years.

* You can use this information to determine how much panel you need.
* In our example. We know that our draw will be 84 Watt/Hours a day
- We need a panel that can generate 84 Watt/Hours a day with MY Peak Hour value
- We also need to keep in mind the charging of the battery. The more power OVER than number, the faster I'll charge a depleted battery.
- I also like to give myself a margin of safety to account for inefficiencies. (I use 20%)

In my location in San Francisco, the worst-case Peak Sun value is 3.6
- That means I can expect MAXIMUM solar exposure for a minimum of 3.6 hours a day
- I have two 90Wh batteries to fill and 84Wh of draw, but only 12.6 Watt/hours of that draw (3.6 hours x 3.5 Watts/hour) will come from the solar panel, the rest will come from the battery.
- I also want to account for the inefficiencies of the system. (I'll add in another 40W/h)
- That means I want a Solar Array that can give me ~240W/H in those 3.6 hours of Peak Sun.

I actually have a 240W/H solar panel… which means I am WAY over supplying the Pi!

Choose your Solar Charger
- You need a unit that will support the total wattage of your Solar Panels AND the total draw of your electronic devices.

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