Summary: <br> Interview with Sara F. Hathaway, Book “Day after Disaster”<br> <br> <br> Episode 13<br> Why are hydroelectric generators so highly recommended?<br> <br> Micro-hydro is one of the most efficient forms of electrical power generation.<br> Lowest Cost per Watt of any other power generation.<br> It is fairly easy to predict what your output would be year round, which can result in smaller battery sizes.<br> <br> They do have some problems:<br> <br> It only provides power with good flow with a decent amount of head pressure, which means it will cause problems for low flow or low elevation locations.<br> Often I have seen that the spring or river needed is a long distance from the home it is meant to power. This gets extremely expensive with wiring because copper is so expensive<br> They are mechanical in nature, so they do break after a while.<br> <br> What are the basic mechanics of hydroelectric generators?<br> <br> Water is used and directed into blades called a turbine.<br> The turbine spins and is connected to a shaft which spins a motor, sometimes direct coupled and sometimes using belts for converting low speed high torque inputs to high speed low torque outputs to the motor.<br> How is the power converted from the generator to a useable current?<br> The generator, if bought is usually a DC alternator generator. This is just an AC generator with a one way switch on each phase.<br> If built, the generator is usually AC, but then sent to a rectifier to convert it to DC.<br> The DC is then usable by an inverter/charger which decides to either convert the DC to AC to be used, or to dump it to a battery bank for storage. This same device can convert the stored capacity to AC to be used when generation is down.<br> Sometimes the controller will have to dump excess to a resister element. There are actually hot water heater elements that were designed to convert this wasted energy to heat such as the <a href="http://www.amazon.com/gp/product/B00KLKO12C/ref=as_li_tl?ie=UTF8&camp=1789&creative=390957&creativeASIN=B00KLKO12C&linkCode=as2&tag=prepperpodcastlist-20&linkId=KMWU2MX5LXAQPDA5">600 Watt 12 Volt DC Submersible Water Heater Element</a> that I found on amazon, you can actually use an ac heater element, but as you drop voltage on those elements, you almost reduce the wattage rating by 25%!<br> There are other ways to use a basic charge controller and consumer grade inverter as well. It would be a little cheaper if you knew what to look for, but it can be a little more complex.<br> What would be an easy way to create this system in a long term survival situration with only the materials you could scavenge?<br> I have seen things built in buckets, using CDs and styrophone, and even articulated PVC devices, but I don’t think most of these are feasible for the type of systems I would build.<br> Probably the best build would not be what you would call “easy.”<br> One of the best builds would be a large waterwheel with a gear-ratio change driven by belts or handmade gears.<br> The awesome thing about waterwheels is that you can couple them up to an alternator or even a mill for grinding grain.<br> The same wheel could be used to drive a pump that will pump water a long distance… at low flow rates.<br> If you were wanting something you could use until that was built, you could probably modify a bicycle to run an alternator, with a battery bank, and be very careful how you use your power.<br> In our current world, if you wanted to reduce your electric bills by using hydro-electric power, what type of system would you build?<br> The very first thing I would do it to make my home more efficient first. Biggest bang for your buck.<br> Then I would look at what my situation is. <br> <br> Water flow<br> <br> spring, river, waterfall.<br> <br> <br> Is it year round or seasonal<br> How far am I from the source?
