Does your research or work take you to remote locations where electrical power is limited or non-existent? I'm not talking about just having to run an extension cord across the parking lot to the nearest outlet...more like needing to provide reliable power for a research camp on a small island in Alaska, accessible only by boat or float plane and over a year in duration. I would like to share the experience I gained from implementing and maintaining this field camp power supply.
That was the scenario one graduate student and I, a field biologist and research technician, faced. Let's just say we had no trouble charging important equipment such as radios and satellite phones or using laptops for data entry & analysis (and maybe a couple of movies).
I would like to share the experience I gained from implementing and maintaining this field camp power supply and will be specifically talking about: types of power sources available for use in remote locations; the basic concept of how these 'sources of power' work; a few simple ideas to help you design a power supply unique to your situation and finally some basic equipment and tools to include in your power supply design.
TYPES OF POWER SOURCES
1. Photovoltaic panels or known more commonly as solar panels: single or multiple panels collecting light energy from the sun, and converting to electrical energy and fed along a cable to be stored in a bank of batteries. Our 400 watt (W) solar panel produced 0-8 amps (A) on average.
2. Portable wind turbines: relatively new in the market of portable power sources but I predict they will get better and more accessible sooner than later. Basically electrical energy is converted from wind power turning a turbine and fed along a cable to be stored in a bank of batteries. I've researched different models and found varying output ratings but the common range for a 400 watt model is 50 to 60 watts or 3-4 amps.
3. *Gasoline powered generator: gasoline powered electrical generator that can be used as your primary power source or as a backup or supplement to another power source. Our Alaskan field camp power source included a Honda EU1000i gas generator in conjunction with a 400 watt solar panel. Gas generator models can range in output power (1000 to 5000 watts: 8.3 to 41.6 amps)
*Remember- account for transporting, storage, usage and re-supply of fuel when using this power source.
4. Portable hydroelectric generator: large scale hydroelectric power is nothing new (there are a lot of dammed rivers out there) but commercially available portable versions of this technology are. In 2010, Bourne Energy made available the Backpack Power Plant-Type 1 BPP-1 (a subsequent militarized version, the BPP-2 has also been recently released.) According to reviews, the BPP's provide clean, quiet power from any stream deeper than four feet, and produces approximately 500 W(40 A) per unit in optimal river flow rate of 2.3 (7.55 ft) meters per second; units weigh less than 30 pounds and are three feet in length.
BASIC CONCEPT
All of these sources can be thought of as the methods for collecting the energy you want to store and ultimately use in your camp. So where does the energy get stored you ask? In a bank of at least 2 or more 12 volt, deep cycle marine batteries. Think of your 'bank' of batteries as equivalent to a bank account, to which you can continually add energy collected from whichever collection methods you decide to use and ultimately 'draw from' to power devices such as laptops, radios, power tools, satellite phones or just general battery charging.
DESIGNING YOUR POWER SUPPLY--YOUR UNIQUE SITUATION
When initially designing your power supply, you need to know your location. What's the local climate? How much sun, wind, cloud cover, rain does your location get? How does all that change with different seasons? How long will you be in this location? Will you be able to access fuel for generators? Is there a stream or river to use a hydroelectric generator? These are just a few examples of what you need to consider when setting up remotely and really need to put some thought into all the possible scenarios you may encounter... better to do it in the comfort of your home or office than finding out it's not going to work while in the field where your options are limited.
What I'm sure you'll find after doing some background research on the types of power sources and what unique site conditions you'll be operating under is that you'll want to use a combination of more than one source. For example, in our field camp it was necessary to have a gasoline generator in addition to the solar panel we set up to collect and deposit energy to our bank of batteries. Knowing there was only so much energy the panel could collect and that was only when it was light out and only in certain types and amounts of cloud cover! Again, the emphasis here is to do the necessary background research in to what YOUR unique situation is.
BASIC EQUIPMENT & TOOLS
1. Power source
2. Cables:
i) Connecting source and load (battery bank); depends on distance needed, usually 12-15 gauge.
ii) Connecting your 12V batteries together (battery bank); 4 gauge.
3. 12 volt, deep cycle marine batteries
4. A Charge Controller. is needed to prevent overcharging of the batteries. Proper charging will prevent damage and increase the life and performance of the batteries.
5. The Power Inverter integral part of the system. It makes 120 volts AC from the 12 volts DC stored in the batteries. It can also charge the batteries if connected to a generator or the AC line.
6. Voltmeter
7. Wire strippers, pliers, multi-driver
8. Extra butt connectors (wire to wire connect)
9. Sandpaper - used to clean battery terminals for good contact
10. Distilled or demineralized water ONLY to replenish batteries
11. Silicone & calk gun --to waterproof electrical connections exposed to weather
