Solar, Field Day, or Emergency Response: Emergency Power Options

1. Solar, Field Day, or Emergency Response:Emergency Power Options George Ure AC7X

2. Agenda • Outage Scenarios: When could the power fail? • Power demands are band and mode dependent • On-the-fly power • Introduction to Generators • Battery Basics – Charge and Discharge Parameters • Battery-powered Options • Inverters • Inverter/Chargers • Grid-Interactive Systems • Wind Machines

3. Where’d I Learn About Batteries?

4. Power-Outage Scenarios • Drunk driver hits a power pole • (1-12 hours) • Earthquake (New Madrid?) • 1 Day – 1 month • Terrible weather event (Sandy-class) • 1-day to 2-months • EMP/Regional Nuclear Event/Bio war • ??? • Field Day: Till the beer runs out?

5. Emergency? What to Plan Power For… • “Crisis Lite” 1-4 Days • Almost ALL hams with a handheld are set! • “Regular Crisis” 5 Days to 5 weeks • 30% of hams are ready? 1-5 recharge periods • Major Crisis 5+ Weeks • 5% or less are ready: Ongoing recharge requirement is harder to meet

6. KEY PLANNING POINTS • Emergency Power requirements depend on: • Expected duration of emergency • Bands which will be used in response • Role of ham using equipment • Net control talks more, needs more energy • Traffic handlers need more, too! • Antennas, transmitter power, various losses

7. Example Emergencies • Semi/Local: (Ike passing through, Joplin) • Mostly VHF/UHF – scattered HF • Quick recovery period – external aid coming quick • Regional: (’64 Alaska quake, supply lines disrupted, regional coms down) • V/UHF for impact areas • HF Health, Welfare, and News from ‘outside’ Phone patch? • EMP/Nuke War/Massive Solar Flares: (still ahead?) • Mainly HF – most repeaters/grid would be down long-term due to the grid impacts, most repeaters gone in a week.

8. Reacting to the Disaster

9. On the Fly Power Don’t forget the cable to connect to the radio! • Alligator Clips are your friend: • Some open 1” wide • http://www.caltestelectronics.com/ctitem/143-fully-insulated/CT3251

10. Language of Power A “Cell” is a single chemical reaction device. • C cells, D cells • AA cells, etc. A “Battery” is a collection of cells “Cells” are measured in volts/per cell “Batteries” are measured by terminal voltage

11. A Cell vs. Battery A single cell is just like a polarized capacitor: EXCEPT instead of a dielectric there is a chemical reaction which delivers or absorbs energy!

12. Batteries (Collections of Cells) Key Terminology to be aware of: Energy Density: The “work to weight” ratio. Cycle Life: How many discharge/charge cycles will a given battery deliver? Discharge Rate: How many hours will a battery deliver how many amp? Typically 20 min., 1-hour, and 20-hour rates are cited. Depth of Discharge: What is the recommended level of discharge beyond which cycle life rapidly declines? Peukert Exponent: Effective shrink rate of a battery at high rates of discharge.

13. Dry Cell Basics Dry Cells: Metal cap Plastic Seal Expansion Space Porous Cardboard Zinc Can Carbon Rod (center) Chemical “Goo” Major difference between cells is the chemistry of the “goo” and whether the chemical reaction is reversible!

14. Where Lead-Acid Battery Electricity comes from during Discharge…

15. What a Completely Discharged Battery Looks Like

16. Batteries Don’t “Die” – They Are Murdered!

17. EQUALIZING Restores Capacity

18. How to EQUALIZE Never attempt to equalized SLA – sealed lead/acid batteries!!!!!! They tend to blow up. Use plenty of ventilation (outside!) because Brown’s Gas is HIGHLY EXPLOSIVE Usually Charging Voltage is increased to drive 2-5% of the battery’s 20-hour rate (in amps) into the battery. So a 100 AMP-Hour battery would equalize at the 2-5 AMP rate for 1 hour. Monitor closely to prevent thermal runaway! Safety timer! Safety Glasses! Do NOT overfill batteries (with distilled water only) if Equalizing!

19. Deep Cycle VS Starting Batteries Plate depth versus toal plate area determines it:

20. Battery Spec Sheet Example Typical good quality deep cycle battery is a Trojan T-105 which is a 6-volt standard.

21. Amp-Hours VS Kilowatt-Hours • Amperes of current for X number of hours • BUT Battery voltage declines over time • SO Ending energy is different than starting energy: • 13 V times 10 AMPS = 130 WATTS • 11 V times 10 AMPS = 110 WATTS • A Watt-Hour integrating meter is what measured actual ENERGY (work done) • 1,000 Watt-Hours = 1 Kilowatt-Hour

22. Battery Rules for Hams Terms like “cold cranking AMPs” is only marginally useful as comparison information. Most ham gear will operate to 10.5 Volts Operating to 10.5 V was required for marine SSB type acceptance 10.5 V is when a 12V battery is “dead”

23. Peukert: Shrinking Battery Effect Batteries deliver less total energy on their way to 10.5V “dead” if discharged FAST Where Cp is Peukert Capacity and both i and t are time and currents of two different discharges such as 10 amps for 20 hours (20-hour rate) vs. 20 amps for 1 hour (1-hour rate). The n is the exponent value.

24. Typical Exponent Values for 100 AHr

25. Ideal Charge Curve (Proctor et al)

26. Battery Temp Compensation

27. Sample Cycle Life – T-105

28. Percent of Capacity Drops When Cold!

29. One More Rule Here’s what a T-105 weighs: If you are down to two batteries in your shopping, pick the heavier battery if you’re after long cycle life – heavier means more plate material is being used!

30. Feed Battery Banks Correctly!

31. How to Charge Batteries Multiple Choices: From a gen-set: Simplest is a chain saw motor on a piece of plywood connected via a drive belt to an alternator. Add voltmeter and whatever if more control is needed. From Solar From Wind

32. Why Wind is a POOR Choice In Texas! Works good on a sailboat – such as the one we lived on. BUT no significant power below 10 Knots/ 12 MPH Generates some noise, besides PWR Depends on swept area – bigger is better on wind gens.

33. Main Problem with Wind is?

34. Solar is GREAT HERE!

35. 4.5-6.5 kWHr’s / M2 Per Day Solar is not initially cheap, but over the long term is does have good payback – breakeven at between 10-18 years depending on how much you do yourself.

36. Solar Has Many Pieces The Panels Charge Controller Battery bank Grid-Interactive inverter

37. Kinds of Mounts Simple (fixed) Single-Axis (panels are mounted on hinges so from March 21 to Sept 21 they are at 20° tilt otherwise (wintertime) they are at 45° Highest priced: Full tracking systems Which track E/W I chose T-Post and Rebar for ours…

38. Small Scale Solar Example Components are: Panel, Battery, Charge Controller. This plus an old ATV winch raises and lowers my tower. Low NO maintenance!

39. Projects You Can “Bury” Solar In… HOW TO SELL SOLAR TO A SKEPTICAL XYL: • Solar-power driveway and outdoor lighting! • Battery “topper-upper” for RV or other battery use which gets infrequent use: • Tractor, ATV, Go Karts, Motorcycles, Lawn tractor… • “Helping the environment!” “Global Warming!”

40. Generators • Basic choices: • Gas (get avgas?) or Diesel (works in tractor) • Ham favorite is the Honda 2 kW with inverter mode which varies engine speed to load • Conventional generators are much cheaper. • In gas generators, consider a good oil additive like AvBlendwhich is FAA Approved: AvBlend.com or AircraftSpruce.com

41. Operating Highlights • Pop for electric start if over 2 kW! • If using for your home, have electrician put in a transfer switch • Best quality choices: • 2 kW & Under: Honda • 2-6 kW – Onan or other RV type are good • 6 kW up: Tractor PTO Type - • 6 kW+ Isuzu diesel

42. Basic Rules & Axioms for Gens RUN-TIME EQUALS FUEL AVAILABLE Natural gas gens require lots of fuel but are a very long-life option. Bad choice though if concerned about earthquakes or infrastructure damaged.

43. Some Notes on the Honda EU2000i Very good unit reports WA7BRI – he uses the Econo Mode with Icom 7000 and now voltage sag problems from key down to listening. ‘BRI meticulously runs every month and uses STABIL in his gas, however! Runs 8-12 hours on a single fill in contest setting, 100 watt xmt class, no RFI issues

44. How Big a Genset? From Onan manual good list of watts. Applies whether your are planning an inverter off batteries (sep. charger), solar (big or small) or buying a genset. Add up peak loads and that’s your sizing. More loads = More $$$

45. Other Goodies from the Onan Manual

46. 2.8 kW Onan Generator Fuel Consumption Typical 24-hour contest time: 6.7 gallons at 50% load. Full Power 24-hours = 11 Gallons per day Full load uses almost 3 times fuel of no load.

47. Generalized Fuel Consumption Ballpark: 50% load is 60% of max fuel use

48. Generator Time to Charge Batteries 85% of charge in Battery size divided by generator/alternator output. Example: 100 AHr battery will be 85% full in one hour on 100+ Amp alternator or generator-run source such as charger. Last 15% of charge takes about 2 ½ Hrs. regardless of size – “absorption charge rate” also called “finishing” charge.

49. If on PURE Battery Source Operate initially from 100% full to 60% depth of discharge. Recharge to 85% of charge level Resume ops to 60% depth of discharge The 85% down to 40% of capacity is the “sweet spot” where batteries give up – and accept charge most readily.

50. Don’t Get Fooled by an Ammeter When charging begins, battery may not begin charging right away. Reason: Takes time for the battery chemistry to “change directions” Delay in discharge to charging reaction is called ‘Coup de Fouet’ by battery gurus. (“crack of the whip”) Read current after 5-minutes of charging, or so Coup de Fouet is why active (charging braking) on electric vehicles is so problematic – energy can’t just “reverse and save” – takes time!