Know How... 91 (Transcript)


Download and watch the episode here:
Know How... 91

Netcasts you love, from people you trust. This is Twit!

Bandwidth for Know How is brought to you by cachefly.com

Know How is brought to you by shutterstock.com. With over 30 million high quality stock photos, illustrations, vectors, and video clips shutter stock helps you take a creative project to the next level. For 20% off your new account go to shutterstock.com and use the offer code, KnowHow 514.

Today on Know How we are going to teach you all about a solar powered Raspberry Pi. I’ve got some evil goat mods coming for you and Brian is going to show you how to get the most out of Mac OSX.

Father Robert Ballecer: Welcome to know-how. This is the show where we build, break, and upgrade. I’m Father Robert Ballecer.

Brian Burnett: And I’m Brian Burnett.

Fr. Robert: For the next 30 minutes or so we are going to give you some of the projects that we've been working on. So that you can geek out in your own private nerve world.

Brian: Yes, we all have our private nerve worlds.

Fr. Robert: Now I've been working on this for a while, ever since some of the people in our G Plus community, which by the way go there right now. You should really become a member. They started saying can you make a solar powered pie? What kind of things can you make solar powered and have them running constantly off of the grid? So I thought maybe we should build one of those?

Brian: Yeah, well it looks like you have enough equipment here for that. But also, that is a very great idea because I just don’t use a lot of power.

Fr. Robert: Very energy-efficient. No were going to get right to this. We are going to show you all the steps that went into making this little bit of the kit. This is very crude, this is very rudimentary that it should give you a net know how to build something on your own. But before that, I was thinking Brian maybe we should indulge our inner motor head. I know you like tinkering.

Brian: I do like tinkering. I like going fast too.

Fr. Robert: Fast. What do you ride?

Brian: I ride a motorcycle.

Fr. Robert: You know there is this innovation that all the cool kids are doing these days. It is called blown engines. Have you heard about that? Now come on, it is injecting more air into your engine.

Brian: Oh! A turbocharger.

Fr. Robert: They are superchargers, right? So a supercharger was a device that connected to the engine. There is actually a spindle connected to your crankshaft that would turn a compressor that would drive more air into your engine, and more power. You get more air, you get more detonation, and detonation is power.

Brian: And who doesn’t want that?

Fr. Robert: And as a motor head, you know that the way to get more power is always to force in more air. So, superchargers. The problem with this supercharger has always been that it robs some of that energy. You are actually using some of the engines momentum to turn the compressor; which we don’t like.

Brian: Oh okay.

Fr. Robert: It gives you the power but it takes away power. The nice thing about his supercharger though is that when you jam on the gas it spins up the compressor really quickly.

Brian: So there is no lag.

Fr. Robert: Exactly. People who have a high performance car, or modified cars, would know that phenomena of if they have a turbocharger, you hit the gas and nothing really happens and then….

Brian: All of a sudden….

Fr. Robert: It is annoying at the least. But it is also never good for the car. So we’ll go over to turbochargers. Do you know what a turbocharger is?

Brian: I know what it looks like.

Fr. Robert: It is a little machine that goes in the engine after the exhaust manifold.

Brian: It uses the exhaust gases to spin it spool up to this band that is in there.

Fr. Robert: Exactly. So it is the same idea as a supercharger but the difference is where it gets the energy to turn that turbine. It is still driving the compressor, to push more air in, but it is connected to a turbine which is in turn driven by the exhaust gas. So as the exhaust gas heads out of the car, it turns the turbine which will turn the compressor, which will drive…

Brian: And force more air.

Fr. Robert: The turbocharger is different from the supercharger because it actually is susceptible to that turbo lag that we talked about. Whereas a supercharger gives you the energy right away, a turbocharger is only going to get that energy when there is already exhaust gases flowing through it. Right? And that has always been a problem. The other problem is because I have super-hot exhaust gas right next to the air that I am blowing into the engine, it tends to heat up the air.

Brian: Right. Because cold air is more dense. Which means you get more power from fuel there.

Fr. Robert: And not only that, and you’ll notice if you’re a motor head, that one of the worst things you can do to your engine is to have it detonate out of sequence. Right? Because then you are fighting the actual momentum of the engine itself. It is a really good way to blow pistons and crack crankshafts; bad things happen to people with premature detonation.

Brian: Oh yeah. I can say that talking to a few of my friends who were experimenting with turbos in high school.

Fr. Robert: Is this “your friends”?

Brian: No, I never owned a turbo but I watched plenty of my friends blow up their cars with them.

Fr. Robert: Exactly. And that is because if the air going into the engine is too hot the minute it mixes with the fuel it is going to detonate. And if it doesn’t detonate at the right time in a four stroke engine you actually have pistons fighting each other. Mortal combat in the engine.

Brian: Fatality in the head gasket.

Fr. Robert: So have you paid attention to the F1 at all?

Brian: I know about F1. But I haven’t followed it religiously. But it is pretty interesting. You were saying there is a pretty big advancement with Mercedes?

Fr. Robert: Yes. So they are all about the turbocharger. And actually they use an advanced version of the turbocharger that has a small electric engine. A motor. So that it can spin up the turbine more quickly. So it is like a hybrid car but it uses that energy to turn the compressor before the exhaust gas gets to the turbocharger, which means it reduces the lag. It gives you the reduced lag of the supercharger but then it gives you the efficiency of it turbo charger.

Brian: Sounds like the best of both worlds.

Fr. Robert: The best of both worlds. Except Mercedes pushed it one step further. This is why I wanted it on Know-How because it is really a cool advancement. And I actually want to work on something like this.

Brian: Yeah, you want to make your own?

Fr. Robert: Yes. They are doing this thing called a split turbo. What that means is they have taken the turbine, which is the part that is turned by the exhaust gases and they have put it at the back of the car. Where the exhaust is. And that makes sense. They have taken the compressor and they put it at the front of the car where the air is actually coming in.

Brian: So they have effectively separated them. And then they can control the hot and cold?

Fr. Robert: Yeah, exactly. So you can keep the hot side hot and you can keep the cold side cold. Which means, the air coming through the compressor is going to stay cooler but here is the cool part. Here is the genius part. They have connected the two with the flexible shaft. So you can have the power stage in the back and you can have the compressor stage in the front. They are working just as if they are together but now you get all the advantages of the turbocharger, a supercharger, a hybrid and a system that keeps the cold air cold.

Brian: Oh wow. And so Mercedes has just been dominating the season, I heard.

Fr. Robert: They’ve been dominating everybody.

Brian: I’m not an F1 expert, from what I heard Mercedes wasn’t really doing that well for the last few seasons and then all of a sudden some magic happened and they are like kicking butt.

Fr. Robert: Exactly. Now Dave points out that you need an intercooler. The system that we explained is really simplified. Most teams will use some sort of cooling device that will cool the air getting pushed into the engine. But if you start off with cool air to start off with, then…

Brian: Then you only need a small one. So less weight.

Fr. Robert: Less weight. That’s one of the things where every other team on the F! circuit is rushing, and copying the design. But it is going to take them some time.

Brian: Well I think now that this season has already started, they are pretty much stuck with the engines they have right now. So Mercedes is going to have the advantage for the rest of the year, at least.

Fr. Robert: Now, I want to ask you, I have actually got a compressor, a turbine, and I’m asking someone if they could help me build a flexible shaft and I'm wondering if maybe we could…

Brian: Put that in the Pope Mobile?

Fr. Robert: Charge your bike.

Brian: Charge my bike. Right. That is exactly what I want to do is test that out on my bike!

Fr. Robert: That would be a great Know How; Maybe the last one but it would be great.

Brian: Maybe not my bike, but you don’t have an extra Pope Mobile around or something?

Fr. Robert: No.

Brian: You could pope it up. You need that bulletproof glass and lets add some turbo to it.

Fr. Robert: I do want to revisit the gear head staff. Because I actually, the world of automobiles, the world of auto tech is absolutely fascinating. I really want us to start getting into it. And I think now that you are on board, it gives us an entrée into it.

Brian: I don’t know if I will sacrifice my bike just yet.

Fr. Robert: You know, Burke has a bike.

Brian: Oh that’s right. He wouldn’t notice if it just disappeared for like a week right?

Fr. Robert: He falls asleep downstairs.

Brian: Yet, he’s not here. We can do that next week.

Fr. Robert: Now before we move on to the solar powered Pi segment I thought it might be a good time to go ahead and talk about the first sponsor of the show.

Brian: Oh that would be Shutter Stock.

Fr. Robert: Shutter stock. Now we welcomed them to Know How. they haven’t been sponsors before and we’re so glad to have them on board because we are creative people. We like putting stuff together. We like advertising what we do. And we like showing people our work.

Brian: And I just like looking at pretty pictures to. I could browse a bunch of hippos. I could do a purple hippo. And a bunch of stuff comes up from that.

Fr. Robert: I guess you could do that, but I’m thinking that shutter stock is such a high quality repository of data and of vectors…

Brian: Don’t limit yourself to hippos!

Fr. Robert: That’s like saying oh look I’ve got this from Re: I’m going to drive it to the grocery store. Right? No, no. Seriously folks, if you are a creative professional and if you want to add a little piece as to your projects, if you want a good place to start looking to drive your creative juices, you’ve got to start with shutter stock. Now at shutterstock.com you will find the perfect image and video for your next creative project. Whether it is for your website, a publication, an advertisement, a video or any other type of project you will find it at shudder stock. You can choose from over 30 million high quality stock photos, illustrations, vectors and video clips.

Brian: That’s what I’m talking about.

Fr. Robert: And even the cranky purple hippos. Shutter stock sources images from around the world and puts them at your fingertips. Shutter stock reviews each image individually for content and quality before adding it to its library. And they add 20,000 images every day. So you are never going to run out of new images to look at. Every time you visit you will find something new. Shutter stock also has flexible pricing. You can choose individual image packs. Or a monthly subscription for the best deal, you can download 25 images a day with the standard subscription. And you can download any image in any size, and pay only one price. Shutter stock gives you the images you need to bring your creative projects to the next level. And they make it easy. Thank you for the purple hippos. Shutter stock has sophisticated search tools. Which means you can search and drill down by subject, color, file type, and gender. Right now Alex is showing you these purple hippos that really he just typed in purple hippos and boom, there they were! You may think it doesn’t have the stuff you are looking for, but with so many images, with so many contributors they most likely have what you are looking for. Shutter stock is also shareable with light box, you can save images to a light box gallery and then access them anytime and share them with your other team members. They also have an award-winning iPad app. Which is a really popular way to share and search through this content. Search on the go and use it to display images during presentations. Shudder*is also a global marketplace. They have multilingual customer representatives in more than a dozen countries an full-time customer support throughout the week. You are not just going to get an email saying we will get back to you before the end of time. They actually know that you need help to get your projects done now, and get them done right. folks, if you are a creative professional, if you want the best in the business, if you want to work with the company that won a webby, you want to work with shutter stock. But I do. Very few can you guys right outer shell or CIA today by psychodynamic account account. If there is no credit card needed, just start an account and begin using shutter stock to help you imagine what your next project could be like. And save favorite images to a light box to review later. Once you decide to purchase, and you will decide, use offer code KnowHow514. That is KnowHow514. New accounts will receive 20% off any package. That is shutterstock.com and for 20% off new accounts use the offer code KnowHow514. And we thank shutter stock for their support of Know-How.

Brian: I just like browsing through their images.

 Fr. Robert: Year just like looking for hippos.

Brian: Well how often do you get to see a drawing of a hippo in a bathing suit with water wings?

Fr. Robert: Now let’s get to something not so strange. Before us is a lot of…

Brian: A mess.

Fr. Robert: A mess, right. I haven't really had a chance to put anything into the project case. In fact, I left everything out because I want people to actually see what goes into a solar project. Now, of course since we are talking about a solar project I was thinking now might be a good time to lead people through the process by which they design there solar projects. Because there is a really good system of steps that you can follow that will help you size your solar panels, size your batteries, and figure out what you can and cannot power. And then also what you can expect out of a solar powered system. Because I know there is a lot of people out there who think, oh just hook it up to a solar pack.

Brian: And it should work right away.

Fr. Robert: There is just a little bit of forethought that has to go into it. Let’s explain how. Okay so the first thing I want you to see is the materials you are going to need. Of course you are going to need some solar panels, but you don’t want those right off the bat. You want to listen to us first so you know what kind of solar panels to look for. You are also going to need what is called a solar charged controller. I’ve got one right here. This one I bought on Amazon for $7 and all it does it allows you to hook up a solar panel, a battery and then a load. It balances between them. It takes in power from the solar panel and either charges the battery or provides power for the load or pulls power from the battery into the load. It is kind of your switch. This is the thing that makes everything go. Now you are also going to need a battery of course. Because the problem with solar is it only works when it is sunny outside.

Brian: Which is perfect here because the weather has been great.

Fr. Robert: If you live in a place like California, fantastic. But you are living in a place that only has a few hours of sun you are going to be depending on the battery a whole lot. Even in a place that has a lot of sun, there is night.

Brian: So before you even start this project you should probably figure out where you are going to put your panels. You’re going to do an exterior thing on your house or something.

Fr. Robert: That is one of the things we are going to look at. We are going to look at where you should be placing panels and honestly whether or not a solar powered system is going to work for you really depends on where you live.

Brian: So for those of you living in a bat cave, don’t try this. It’s not really going to work.

Fr. Robert: No, you won’t be happy. Now you are also going to need some way to convert the power into something usable. This is a standard cigarette adaptor. You’ve got 12 volts going in and 5 volts going out. The reason for this is that there are a lot of solar systems out there. Especially smaller ones that either operate on 12 or 24 volts. I’ve defaulted this one for 12 volts. You need to be able to take that and turn it into the power that is usable by your device. Now if you’ve got 12 volt devices, you are good to go. Just plug it right in and power it up. The Pi is 5 volts.

Brian: 5 volts, 2 amps.

Fr. Robert: It is a little lower than that. It is 5 volts, 750 ML amps. What is particular about this is that you need to find a way to get the voltage of the system down into the voltage of the device that you are going to use. We’ll have more on that later. You’re also going to need tools. Snips, screwdrivers, you’re also going to need this. It is a multimeter. Don’t buy an expensive one. I kind of like the expensive ones, but I never carry them with me. I kind of like having some cheap ones that I know I can break. You just need something that is going to tell you voltage. We are working with power and it is good to be able to know how much power is running through a system. It’s not just for building, it is a safety issue.

Brian: It would probably be a good idea for this project. So okay, we’ve got the tools we need. We’ve got all the parts, what is next?

Fr. Robert: Well how about this? Let’s talk about your drawing of the device. You hinted at this before. You need to find out whatever you are going to go to solar power you need to find out how much power it draws. That ultimately is going to decide what kind of batteries, charger and solar panels you need. Now in most devices you are going to find that in the spec sheet. For example let’s say you wanted to find what the draw is for you Motorola phone. You could go to the Motorola website and go to the specs for that particular device and it will typically say something like 5 volts, 2 amps and that gives you the draw. Now for people who have studied a little bit of electronics you know West Virginia.

Brian: Why is that?

Fr. Robert: You know West Virginia.

Brian: I know where it is.

Fr. Robert: I’m not talking about the state. West Virginia is the easiest way to remember how we determine watts, amps, and volts. It is W=V times A. Watts equals volts times amps. I know I told you there wasn’t going to be any amps but I lied to you. This is how we determine how many watts something uses. In the case of the Pi, I know that it is a 5 volt device because it is running off of USB. I also know that it’s going to draw a current of about 700 ML amps. So if I want to know how many watts it is going to draw, I multiply 5 volts times 700 ML amps and I get about 3.5 watts per hour. That is how much power this thing is going to draw.

Brian: Alright, but what is the difference between amperage and voltage?

Fr. Robert: Thank you for asking. A lot of people get this confused and I don’t want to give you all the mathematical/engineering terminology because that is going to confuse you even more. The example I used to use with my students is this. Imagine you have a pipe. That pipe is one inch wide now lets say that the width of the pipe is the amount of the current it draws. The height of the pipe and where it contains water is the voltage. The voltage is all about differential. So from 0 - 5 I get 5 volts, from 0 - 12 I get 12 volts. It is the difference between two points on that electrical circuit. If I have a circuit that does 1 volt and 1 amp, imagine a pipe that is one inch wide, one inch high and it is filled with water. Now let’s say I have 5 volts, 1 amp. Imagine a pipe that is one inch wide and 5 inches high. 12 volts, 1 amp. One inch wide, 12 inches high. Now imagine we increase the amperage. I increase the amount of flow into that pipe. It’s not just the potential from 0 - 12, I now say 5 volts, 5 amps. So it is a pipe 5 inches wide and 5 inches high. So does that make sense?

Brian: That makes sense.

Fr. Robert: It is not an exact analogy so if you go into an Engineering class and you get that back they are going to laugh at you, but it is actually a really good way to understand how power actually works.

Brian: That is a good way to explain it. My Dad works for PG&E, which is the electrical company out here in California, and he’d probably be very disappointed that I didn’t have a better understanding but that cleared up a lot of stuff for me.

Fr. Robert: Although 8662 has said in the chat room that it is not a very good idea to put electrical wires in a water filled pipe.

Brian: A water filled pipe. Yeah, that’s true.

Fr. Robert: Alright. Let’s get back to solar. Now we know our draw. So this device is going to draw 3.5 watts every hour which means that over the course of a day it is going to pull something like 84 watts. So that is my day total. Again I always calculate for worst case scenario. That is if the Pi is running full out, full tilt the whole day it is going to pull 84 watts. Realistically? It is not going to run full tilt the whole day and it is probably going to be closer to 40 watts the whole day.

Brian: Yeah, because you can’t be playing games on it all day.

Fr. Robert: Exactly. The other thing is that whenever you are sizing solar systems, always account for worst case scenario. Unless you don’t care if the things shuts off.

Brian: That would be kind of a pain. Especially if you are trying to run a little server on it.

Fr. Robert: Now that we’ve got the draw, we don’t actually look at the solar panels yet, we look at the battery.

Brian: Because that is where we are going to be storing our energy.

Fr. Robert: In fact right now this system is completely devoid of power. I don’t have any external power going into the system so it is just running off of battery. As you can see, the Pi screen is on. Can you show us the output screen from the Pi Alex? It is because I didn’t hook up a mouse.

Brian: It isn’t touch sensitive? Just unplug it and plug it back in?

Fr. Robert: You don’t do this. Don’t ever do that to a Pi. Okay. So it is drawing everything off of the battery. What we would like to do is we would like for this device to be able to run even if I don’t get sun. So let’s say I have cloudy days, rainy days, night time. I size my battery by how much back-up time I want if I don’t get sun. In this particular case I’ve configured this so that I can run one day if I get no power for an entire day, no sun whatsoever. Or let’s say the solar panel broke this battery is big enough to power the Pi for one day. At full load.

Brian: Cool. Did you do some calculations for that?

Fr. Robert: I did. All batteries are rated, so this is a 12 volt battery, 8 amperage. Which means West Virginia and that gives me 96 watt hours. So it is more than a day and it should keep me up and running even if I have full draw.

Brian: Full Raspberry Pi draw.

Fr. Robert: It is up to you on how you want to design your system. Some people will only want to account for the night and assume that they are not drawing for a full. So you could get a battery half the size and panels to charge the battery. I’m always paranoid and I always like having extra power. Honestly this panel here can provide in full brightness, 10 watts of power. So this would be enough to charge the Pi at full tilt and still give about 6.5 or 7 watts back to the battery per hour of sunlight. But we are going to talk about sizing. Alright. So that gives us our battery. One quick note on this. If you are going to do this project, please get a dedicated battery for this kind of system. You want a deep cycle battery.

Brian: What does that mean?

Fr. Robert: Okay, so the battery in your motorcycle. That is designed to provide a lot of power but it only does it very briefly in that it recharges. If you take that battery all the way down to empty it isn’t coming back all the way.

Brian: That’s happened to me before too. I’ve left it outside and when it gets really cold it gets drained all the way.

Fr. Robert: Or people who leave their car lights on overnight. Those batteries aren’t designed to be taken all the way down and then all the way back up. They are designed to give big bursts of energy and that is it. So if you buy a deep cycle battery it is going to cost more but it will actually last. Because remember we are counting on this thing to power the Pi. It is going to be draining at least half way down every day.

Brian: Because there is night time. So do you know how much this one costs?

Fr. Robert: This one I actually stole from Jammer. So I don’t know. If I bought this online it would be about $12. It’s not bad. Shipping actually hurts more than the battery. So I’ve got my battery now and now I need to calculate my solar paneled needs. Again this going to depend on how much power I want going to to the system, you’ve got the 10 volt panel there, that won’t do it. That is not going to do it. Imagine this. I need what is called the peak hour number. If you search peek solar hours for your area you’ll get a number that gives you the average amount of sunlight in your region that works out to 1000 watts per square meter.

Brian: Okay. And that gives you the hours?

Fr. Robert: It is an equivalency number. So for example in San Francisco I get 3.6 peak hours. If you add up the solar radiation that hits a certain area there is 3.6 hours in which I will get 1000 watts out of every square meter of space.

Brian: Okay.

Fr. Robert: That is actual a very useful number. We may think we saw the sun for 8 hours but that is not true. The sun comes at different angles, sometimes you get a lot of radiation, sometimes you don’t get that much. The equivalency number gives you a really good number to base the size of your panels.

Brian: You can calculate how much power you are going to be able to store.

Fr. Robert: And how much power you are going to need. You need to be able to input enough power, not just to power the Pi but also to charge the battery.

Brian: Right. So this gives you an idea of how many solar panels you need to get or how bit they need to be?

Fr. Robert: Right. Now for example. In San Francisco the worse-case peak sun, the worst possible month during the year is 3.6 peak sun hours. So it will never go below that. So I build my system for worse-case scenario because I never want this to shut off. So that tells me that if I have two 90 watt hour batteries to fill and I have a Pi that draws 84 watts per hour I know that I’m going to need somewhere in the vicinity of like 120 watts generated per day out of the peak sun hours. And the reason why I get to 120 is because I always build in some numbers for inefficiency. You are going to lose a little bit of power every time you transfer between devices. Between the battery and the charger, the charger and the converter, the converter and the Pi. Now, I can get away with 120 watts of solar panels per day. I don’t like doing that. So instead.

Brian: Is that big enough for you?

Fr. Robert: I went with this instead. This is an old BP solar panel. It generates 240 watts and the nice thing about this is that since it is using smaller cells I don’t have to worry about things like shade. A lot of those really big inexpensive cells, if you get shade on any part of your ray it dramatically cuts the efficiency of the ray.

Brian: So what makes this one special?

Fr. Robert: This one is special because it uses super high efficiency crystal line cells. And it’s got them divide so that if I lose part of the ray to shade, the rest of it actually still generates.

Brian: It’s segmented.

Fr. Robert: So this one will give me about 240 watts between 12 and 30 volts.

Brian: How expensive was this?

Fr. Robert: I stole this.

Brian: You don’t pay for anything do you?

Fr. Robert: Actually there’s a Jesuit house in Honolulu that doesn’t have solar panels anymore. But okay. Actually let’s put this one back. So the reason why we have the solar charger is because we need something to regulate the flow of power from this solar panel into our system. So what is going to happen is that it is going to go into our solar panel and into our solar charger. It is going to plug in right here. I’m actually simulating this with this little power supply. So now I’ve got 12 volts going into this. Now it is giving me an indication that it has gone ahead to charge the battery.

Brian: Very pretty. I like LED’s.

Fr. Robert: So now I’ve got power coming into the system and it is using that power both to charge the battery and to run the Pi at the same time. And it the circuit is really this simple. Building itself is not that hard. I have external power, I have a battery, I have a charger and I have the device I want to power. I’m using this 12 volt to 5 volt adaptor to give me the 5 volts I need for USB device.

Brian: Very cool. If you are going to trouble shoot because you pointed out the multimeter earlier, where might you have issues and where would you want to test?

Fr. Robert: So, if you can hold the multimeter. So, the first thing that I want to check is my incoming voltage. I’ve got 11.9 volts coming in which is close to 12 volts. And off the battery if I was to disconnect I’ve got 11.5 volts coming out of the battery. I can also check the load to find out how much is being used. Am I getting 11.5 out to my 12 volt to 5 amp USB adaptor? This is where the multimeter comes in handy because I can also check the voltage coming out of the solar panel to see if it is actually generating power. What you’ll see in a damaged array in a solar panel is really low voltages or really strange voltages.

Brian: And this could just be a defect?

Fr. Robert: Like I had a panel that got damaged and it started supplying 400 volts, but at a crazy low amperage. Something shorted inside and made it useless.

Brian; And if you’re not getting any power at all it is probably because Padre stole your solar panel.

Fr. Robert: If you’ve got a solar system at home and you wondering why you are no longer generating power to power your Pi’s probably because I got the panel.

Brian: Okay, so we’ve got our set up, we know how much power we’ll need to power the Pi, we know how much power we need from the solar panel.

Fr. Robert: This is too big. This provides 240 watt hours which means with my lowest possible peak sun in my area I’m generating close to a KW a day. Neither the battery is big enough to store that much power nor does the Pi draw anything like that, but I want to use the sun. I would like to use the sun and in order to be able to power just the Pi what I’m thinking is that I’m going to be adding batteries, storage capacity, and then I’ll be able to charge my phone. With a KW hour a day I could pretty much power all my computers.

Brian: That is pretty cool.

Fr. Robert: All my laptops, desktops.

Brian: Charge your cell phone and everything? Do you ever have to worry about too much sun? Overcharging?

Fr. Robert: No, that is what these controllers are about. This is a cheap one but if you get a decent controller it will condition the battery. So it will make sure it is not charging the battery too quickly, not discharging the battery too quickly and also it will cut it off if it reaches the point which it knows the battery is full. Some of the higher ends actually have a bank of resistors that will dump off the excess power rather than driving it to your battery and overcharging it. Again, this is a cheap set up. This is what you get if you buy your solar charged connector at Amazon for $7. I actually broke this because I drew too much power through it. It is still kind of working but I would never install it in a place I was worried about fire. In the studio it is cool.

Brian: Yeah, we have plenty of fire hydrants here.

Fr. Robert: Okay. That is enough about solar. I think in the future what I would like to do, I want to put it in a project box. What I would really like to do, I’d love to use the Pi to control a motor that would automatically face the sun. That would be a lot more efficient. A self-contained solar tracker. I like that.

Brian: Yeah, let’s do that.

Fr. Robert: We both play Goat Simulator right?

Brian: Yes. It is a fun game. Ridiculously fun.

Fr. Robert: It is a fun game. So I was thinking the folks at home needed to have a little one up for some Goat Sim. If you are a casual gamer like myself you probably heard about goat simulator. Is a giant sandbox game that places you in the character of a goat. It uses the unreal engine and has a lot of destructible elements. Well there are three specific mods that I want to teach you how to do. Starting with the angel goat. The angel goat is very very simple. All you have to do is nothing. When you first start the game don’t do anything. Don’t jump around, don’t scare anyone, just be innocent. Because again, you want to become an angel. After five minutes you will see the color of your goat change too white and you will get a halo. What this comes with is the ability to jump. Really really high. Way higher than the default goat. Plus it gives you a power that you can toggle. If you hit and hold R, you actually fall much more slowly than you would with the default goat. The second mod that you can activate is also very easy to get. It is the goat queen. What you need to do is go up this small ladder that you will find in the same paddock that you found it. Once you get to the top and go through that little bit of darkness you will find yourself in a throne room with your subjects bowing down before you. go ahead and sacrifice yourself to the altar and you will respond outside. Noticed now that you have a mask of the goat queen. Now the powers of the goat queen are simple. Hitting R allows you to drop goats from the sky. Sounds a little boring and a little strange but actually comes in handy later on. The last mod but I think you should try to get is the evil goat. The demon goat. Now this is located to the north and the east of where you spawned. You are going to find it right next to the bolder that you can roll down. You know you've hit the spot when you see an eerie red glow. It is the evil altar. You are going to find pictograms on the ground and what you need are five little sacrifices. There are two ways to do this. The first is to be the goat queen. Remember the goat Queen can hit R and drop goats from the sky. well if you go into that pictogram and drop yourself five goats you will be able to activate the evil goat transformation by hitting the one key. Once the evil transformation is done you will be able to activate your tongues of evil which will allow you to stick things to yourself. You will also be able to activate hours of flight. There is also another way to activate this bond. That is by grabbing five innocents from that. Go ahead and head butt your way in and grab five of the innocent ones and drag into that pictogram and do the same thing. Either way you will get your genomic powers. Now I like to have all three of these mods activated at any given time because it allows you to create a lot more mayhem. You can jump high, you can drop your genomic thrones from the sky and you can fly around the map. Give these mods a try and in no time at all you will have mastered goat simulator. I’m Father Robert Ballecer and that was a quick tip. Admit it. You have done that way too many times.

Brian: Oh yeah. I like that you are doing tips on it, because we introduced it if you shows that and people need to know about some of that stuff.

Fr. Robert: You know it is the kind of game for people who may be are tired of just the standard shoot them up type of games. There is no way to win the game, it is just how much mayhem can you cause.

Brian: And you can cause quite a bit of mayhem.

Fr. Robert: You know it is kind of like my my outlet. I like to read YouTube comments and play goat simulator. That is how I’d vent.

Brian: Because you can’t get angry.

Fr. Robert: You don’t want to see me angry. Okay Brian, let’s get away from goat simulator and talk about something truly useful. Because you have got some life-changing mac OS X tips.

Alex: Padre, this is Alex. We don’t have time for this again. You have long run long again.

Fr. Robert: Alex, wait a minute.

Alex: We have to quit.

Fr. Robert: This is ridiculous. We have the full hour. Are you kidding me?

Alex: We have too much going on and we just don’t have time to do this.

Fr. Robert: Just because he’s got buttons in front of him he thinks he has all the power.

Brian: He has gone to the dark side. Maybe we shouldn't mess with Alex. Has a lot of power over us. Do you just kill like a thousand….

Fr. Robert: They are crying out that they're not going to get their Mac iOS X tips.

Brian: Maybe next week.

Fr. Robert: Know I'm done. Fine whatever. I’m tired of getting our segments cut.

Brian: You saw the power he had. It is up to him.

Fr. Robert: Ladies and gentlemen I am sorry I am not going to pressed against the dark Lord of your soul. We are going to have to call the show. We had a lot of information, in fact way more than we talked about. All the solar calculations I actually have in the show notes so you are definitely going to want to go there. We are going to post those up in about 3 hours. Where can they find the show notes page?

Brian: Glad you asked because you can find those at twit.tv/kh and as far as show notes they are the best.

 Fr. Robert: The best in the business. We give you step-by-step so don’t freak out if you weren’t able to follow us during the show. I know it is a lot of information but read up a little bit and I’m sure you will be solar powering your Pi in no time. Also if you are concerned, if you really do have a question about how you make this thing work. You can always email us at knowhow@twit.tv and that email will promptly be put in my spam folder.

 Brian: We will never ever read it.

Fr. Robert: But if they do want us to read something where should they go?

Brian: Well you could go to our Google plus community. We have over 6000 members. In it is a pretty cool place to post questions and people have good responses. But if that is not good enough for you and you use twitter you can always follow us there.

Fr. Robert: I’m @ PadreSJ.

Brian: And I’m Cranky_Hippo. We get those right away.

Fr. Robert: And if you like to vent as to why our tips keep getting cut off. Please, go talk to the dark Lord himself you can find him on Twitter. That is @anelf3 and vent to him and tell him we want our full hour of Know How because I’m sick and tired of prepping stuff that doesn’t go out on screen.

Brian: Unlimited power!

Fr. Robert: As for us, I think that is going to do it. Make sure you join our G Plus page, make sure you give us the feedback. Make sure you tell us what you like seeing on the show and what you don’t and we’ll keep giving you all the Cranky Hippo, Padre SJ goodness.

Brian: Now that you know how, go do it!