Tag Archives: solar

Solar & Wind Electricity

It’s time to talk about using electricity in an Earthship. From the title you can probably surmise that this is about using solar and wind to generate electricity, and you would be correct.

I should add here that renewable energy sources, in general, are what is desired. If you live on the coast and can harness tidal power, that is equivalent to what I’m going to talk about here. Similarly, micro hydro and geothermal would also fall under this category. Solar and wind just happen to be the two most common renewable energy sources.

The vast majority of people these days are familiar with solar panels and wind turbines, at least to a point where they understand that they can be used to generate electricity. There are a number of details to be aware of.

First and foremost, as mentioned before in other posts, an Earthship is designed to be independent. That means not connected to an electrical grid. This independence arose from the basic principle of wanting to create a building that could be built anywhere in the world, regardless of available infrastructure. The advantage to this is that if the grid goes down, you aren’t affected. Conversely, if you have issues with your electricity, you aren’t affecting anyone else. Considering how many times a year we have weather that knocks out the power grid, this can be a big advantage.

Once you start down the path of generating your own power, you need to take on a certain amount of responsibility for that. After all, when something goes wrong you are the one who will have to deal with it. There are some companies that will sell you all of the equipment and hook it all up for you. If something goes wrong you can call them, but you should be aware of what you are buying and what you are getting yourself into. It just makes sense if you want to get the most out of generating your own power.

Solar power is pretty ubiquitous these days. If you are interested in solar, some basic things you should research are: the average number of sun hours per year in your area (called insolation), what your power requirements are, what kind of sun-based view you have available to you and what type of system you are looking for.

When generating your own power, you have basically three options in terms of how to set it up: completely disconnected from the existing electrical grid, grid- tied and a hybrid of the two. Off-grid is pretty self explanatory: you are not connected to the existing electrical grid at all. In the case of being grid-tied, this means that all of the power you are generating is being fed directly back into the grid; you aren’t using any of it yourself. The electrical company pays you for the power you generate and this shows up as rebates or credits on your existing utility bill. The advantage to this is you don’t ever have to worry about using too much power. The downside is, if the grid goes down, so do you. It could be a beautifully sunny day, but if the grid is down, you have no power and you aren’t getting paid for all that power the solar panels are generating because the grid is offline.

A hybrid system is where you have battery backup and if the grid goes down, you still have whatever power you have stored in your batteries to use. It seems like the best of both worlds, but this is also the most expensive way to do it as you need more hardware to handle it all. You also need to have a grid line close by to tap into.

Solar panels come in lots of sizes and power ratings. You should probably aim for getting enough panels to generate a little more than double the power that you plan to use on a daily basis. This will help to compensate for cloudy days.

Wind turbines are a whole different ball game. I don’t have any personal experience with my own turbine, but I have done a fair amount of research and talked with those who have tried it. My biggest piece of advice to anyone wanting to try out wind power is to live on the property where you are planning to install it for at least three years (probably five is better) before getting a system. This will give you some idea as to what the wind is like over many seasons. As always, there are exceptions, such as if you live in a coastal region or the prairies where it is windy all the time then you probably don’t have much to worry about. But in areas like where we live (forested hills) wind is hard to come by a lot of the time. Most of the people I have talked to in the area, including some who have turbines, say it’s not really worth it in our area.

Some other things to consider with wind turbines is that they are motors in motion and as a result of that, they will wear out and break. Solar panels have no moving parts so they don’t have that problem. Also, there will be times when there isn’t enough wind to turn the blades as well as times during storms when there is too much wind and it may destroy your turbine. Remember this if you are in tornado alley.

The vast majority of wind turbines are the horizontal axis kind. Those are the ones with the blades all facing into the wind, like in the picture below.

These are generally speaking the most efficient, because their blades are facing directly into the wind. They also get the most wear and when really strong winds come up, most susceptible to damage.

The main other type is the vertical axis wind turbine. Here is a picture of one they have at Earthship Biotecture in Taos, NM.

These ones are less efficient in terms of the amount of wind the blades capture, as only one side of the axis catches the wind and the other pushes against it. There are lots of online articles about them and I’m sure the technology has changed over time, but this type of turbine are favored by Mike Reynolds. According to him, they take less wind to start turning, don’t spin as fast in strong wind because of that push back effect and last longer without needing repairs. If this is true, then if you amortize the average power generation over time between a vertical and horizontal axis turbine, taking into account down time for repairs, you might come out ahead with the vertical axis turbine simply due to the fact that it doesn’t break as often.

Of course, no discussion of off-grid living would be complete without talking about batteries. Your basic battery used for power storage for an off-grid home is the lead-acid battery. These are the same type used in golf carts and marine settings (boats). These are the cheapest, but by no means are they bad. They do require maintenance, however. You need to keep them topped up with distilled water as the electrical reactions use up the liquid over time. I do our battery maintenance once a month.

You can get sealed batteries and they have gel batteries as well. You may have heard about the company Tesla coming out with a battery solution of their own using Lithium-Ion batteries (the same type in your phone). I have looked into this somewhat as it seemed like a nifty thing, but it turned out to be not as nice as I would have hoped. First, it is not just a battery, as it includes a built-in charge controller, inverter and computer to control the whole thing. This isn’t very convenient if you already have an inverter and charge controller. The system is meant more for a backup/hybrid grid-tied setup. Also, it requires a connection to the internet to function (so they can give you over-the-air updates and monitor your usage). Ummm, no thank you.

There are other options out there as lots of companies are working on battery technology. In the end, it usually boils down to what you are looking for, what is available and what you can afford.

These are all the types of things you get into when you start thinking about going off-grid. For some people it is very interesting and they jump right in. However, there are many others who don’t want to be bothered with it all and just want power when they flip on the switch. Personally, I like knowing how much power we’re making and using and we manage our usage to match what we make.

We have been running our solar off-grid system now for over two years and we love it. We do have a generator as a backup for those long stretches of cloudy days during winter. We wouldn’t need it as much if we added more panels to our system. That will happen eventually when we get our Earthship up and running.

I do apologize for this article taking so long. I have worked on it several times, but it was degrading into long descriptions of Volts, Amps and Watts and I was trying to keep it a little simpler. If you do have any questions about this, feel free to leave a comment.

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Earthship Island, Day 3

So it looks like what’s going to happen with the blogging is Kat and I are going to alternate days. It’s really the only sensible way we can have enough time to make a post. If we both tried to post on the same day, we would spend all day on it and we do want to have time to work on other things.

That being said, today’s post is going to be Earthship technical.

So we showed you what the front of the tropical Earthship looked like last time, now we’re going to look at it in more detail. This first picture is from the side.

The first thing to note is the planters in this Earthship are outside. They are what you are looking at just beyond the bamboo railing. This also means they are part of the berm.

If we zoom in bit you can see this:

This is the outside end of a vent tube. Air it does provide, but the berm does not cool it like it would if the pipe were metal instead of plastic. Also, I don’t think the depth of the planter is quite enough to cool the pipe enough anyway, but to check that we would need some sort of remote, underground temperature sensor. One must also keep in mind that, in situations like this (i.e. building in a country like Indonesia), we’re pretty much building with whatever is available. There are several things in this place that could make a big improvement if only a different material had been used, but you use what you have.

If we head up onto the roof and look back at the planters, you can see the collection trench for the rain water. They used dead coral for the silt filter. There is a tonne of it lying around on the beaches here.

That trench channels the water along to the shown pipe with the screen over it. As the depth of the water increases in the trench, it will eventually drain through this pipe and into the red cistern.

This is a pretty decent setup, but there is one thing that would make it even better. If they had attached the screen to a sleeve that could easily be removed then (a) it would be easier to fix when it is damaged and (b) in the event of a tsunami you could quickly remove the sleeve and replace it with a cap. This would save your cistern from filling with sea water, which in the aftermath, it would be very desireable to have some fresh water, especially on a small island that has no natural source of water.

Unfortunately, the water channeling on the second Earthship here isn’t setup the same as this one. On Earthship2, it is channeled right into the cap of the cistern, which has been removed and a screen installed over top of it. The problem with this is that they embedded the edge of the screen in mortar, which you would think would make it quite secure, but as we discovered, both screens have suffered damage on Earthship2, one of them almost completely detached. With the screens embedded in mortar, this will not be an easy thing to fix. Had they done it the same way as Earthship1, the fix would have been simple.

On to the solar system.

There are four panels for Earthship1 and the system seems to be working just fine. We have DC based LED lights inside, as well as DC water pumps for the toilet and shower. There is a tiny 500W inverter with a single socket on it that we have been using to charge our phones and tablet. No issues to report there.

Earthship2, however, is currently without power. This is because its batteries are dead. We’re not sure if that is going to get fixed either as none of us are going to shell out the big bucks for new batteries. We contacted Earthship Biotecture, but haven’t received a reply yet.

I bet you’re wondering what that big black strip in the middle of the roof is there for? Well, let me show you a better view.

So the idea here is that this long, black metal duct will heat up in the sun and draw hot air into it. The vent tubes should then provide fresh air that is pulled into the main living area that is cooler. You can see one of the curved roof vents at the far end where the hot air is to be expelled.

The problem is there is nary a whisper of air coming from the vent tubes so inside isn’t really all that cooler than outside, especially at night. Things only really cool down if there is a nice stiff breeze blowing through the screen door.

At the opposite end of Earthship1, you’ll find this big black barrel.

This is supposed to provide solar heated water, but it has some flaws. The first one, is it’s made of plastic, so if the sun is shining on only part of it, the rest of the barrel doesn’t conduct that heat because plastic is an insulator. Secondly, not much of the barrel is actually exposed to the sun, so you’re really only heating a small amount of water at the top.

We noticed this when we took a shower today and we had full sun out. The water was almost down right cold. Again, this is probably one of those situations where they used whatever they had available, not necessarily what was most ideal.

I thought I would give you another look at the planters from above. It doesn’t look like they planted any food vegetation in these, just a bunch of grass and other things that were growing close by. We did find an aloe plant growing on the side of Earthship1 though, which for us Canuks who sun burn easy is a great thing to have.

Moving inside, if you look up at the ceiling you’ll find four of these screen vents to let the hot air out.

I you look above the front door, there are two big screen vents. As you can see, the screen is quite damaged. Replacing it will be quite the challenge as once again, it has been embedded in mortar.

This is our shower. It works quite well, though the water isn’t warm. It is gravity fed from the barrel on the roof. There is a pump that turns on to refill the barrel when it finds the water level has dropped.

This is the splash guard wall for the shower. I think all of us here are pretty unanimous on liking the look of the plastic bottles with the ends that look like stars or snow flakes.

This is our toilet. It too is working quite well. It is filled from a greywater well from under the planters. Everytime you flush, a pump comes on to refill the tank.

Lastly, we have the sink. We can wash our hands here, but you don’t want to drink the water as there isn’t a full filtration system setup in this Earthship. We brought a water filter with us so we can fill it from the tap and get drinking water without having to buy water all the time.

That takes care of most of it. There is some minor damage to the walls and floors, which apparently is due to earthquakes. It has made some of the doors difficult to open as a result as they rub on the floor now.

Earthship1 is in pretty good shape, but E2 isn’t. It doesn’t have the same facilities, the power isn’t working, so the pumps for the plumbing aren’t working either. There is no bed or bed frame and no lights, even if there was power. We are supposed to be working on making a bed frame another furniture for E2 but without power or proper tools, this is proving to be challenging.

I should also mention the humidity factor again, as it destroys a lot of things left lying around, especially anything made with iron based metal. Screens are rusted, tools are rusted, Kat found a can of nails that had all fused completely into one mass. It also doesn’t help that there is probably a lot of salt in the air from the ocean being so close by.

Overall, we’ve settled in and getting by, but Katrina’s living quarters are a little less than desireable and we need to improve on that.

Solar Review 2017

Having been living with our solar power now for over a year (installed Sep 2016), I thought I might share a few of the things we’ve learned over the passed year living with it.

I guess one of the first questions people wonder about, for our area, would be “is it worth it?” This question does have several dependencies, but overall, I would say definitely YES! The more we hear about how the cost of grid electricity is going up and up, we are so glad we aren’t part of that. Especially up here where power outages are not uncommon. We never notice when this happens.

The other fun thing, especially during the summer, is that you can use as much power as you want during the day. In fact, this is recommended as this is when the sun is up and your batteries are being charged. Compare that to being on the grid (here in Ontario anyway) where they charge you extra for the power you use during “peak hours”. This always felt like being penalized for working from home.

Of course, whether it is worth it for you will depend heavily on how you expect to use it. Power used is based on energy and time (thus why your electric bill is charged by the kilowatt-hour). If you want to do a lot of work in a short amount of time, you will need a lot of energy. Anyone considering going off-grid should take some time to do some research. Figure out what things you are using right now, what appliances, kitchen gadgets, bathroom widgets, computers, TVs and so on. After you have that list, figure out how long you use each of those items everyday. Add all that up and you’ll get a rough idea of your daily use.

As a heads up, anything that uses electricity to generate heat will be a fairly big power draw. Hair dryers, hair curlers, hair straighteners, hair crimpers, space heaters, electric stoves, electric clothes dryers, toasters, electric waffle irons, clothes irons, soldering irons, electric welders… (you get the idea) will all draw a lot of energy. I put that in bold because how much power they draw will depend on how long they are used for. Unfortunately, most of all of those things I just listed have a long warm-up period before you actually start using it, so that will add to the time. Something like a microwave, which does draw a lot of energy, but it doesn’t have a warm-up time, can work to your benefit. Generally speaking, how long do you really run your microwave? Usually under 5 min. It may have a high energy draw, but it is a short amount of time. Compare that with something like a slow cooker, which draws less energy, but is used for long periods of time and you may find the slow cooker kills your off-grid system. If you can’t live without your slow cooker, we highly recommend a thermal cooker instead.

When we moved up here to the trailer, we knew we would be going off-grid so we did the tough thing and got rid of all of our electric based heating devices. This included a really nice toaster oven we had, which was difficult to give up at the time. Now we don’t even think about it. We only have three solar panels at 250W each so our system isn’t huge. That being said, the seasons affect it big time.

From March until October, everything is golden. We get enough power to handle all of our needs without having to resort to using a generator as back up. This includes things like power tools and vacuums that draw a lot of power. For that stuff, we usually just wait for a sunny period.

From November to February, in this part of the world, it is cloudy more often than it is sunny. Also, the days are a lot shorter, so even when the sun is out, you don’t get a lot of time to recharge the batteries. Additionally, if your batteries aren’t kept in a temperature stable environment (ours are out in the cold), this will impose further energy loss to you for usage as it will take more energy to charge the batteries when they get cold. This is where having a generator as backup is necessary.

We have a little control unit with an LCD display attached to our inverter that tells us various things.

In the above picture you can see that we are in Bulk Charging mode and we have an input voltage coming from the batteries at 58.0V. If the inverter is telling you it is charging that can only mean one thing: the generator is running. When the generator isn’t running, we just have a read-out of what the voltage is coming from the batteries. There are other things we can check, but I find the voltage is the most useful. We have a 48V system and having lived with it for over a year now, I have a pretty good idea of how full the batteries are based on the incoming voltage.

If that 58.0V I mentioned above seems high, it’s not. Think of your batteries like a car tire. If your tire is full at 30psi (around 207kPa) then you will need a compressor that can generate more than 30psi to fill that tire. That’s just the nature of the physics. In addition to that, as far as the batteries are concerned, the colder it is, the more voltage (electrical pressure) you will need to fill the batteries. During the summer, we can top out the batteries at 57V, but during the winter, we can push it up to 62V before they are filled. The charge controller we have handles this automatically using temperature compensation.

Incidentally, that increase in voltage when it is cold comes with one interesting factor: the resistance in the wires drops as it gets colder, so you gain some extra voltage in the winter. If you can keep your batteries somewhere more temperature stable (like a garage), that would help a lot. Lead acid batteries don’t like it when they are cold.

There are other battery options, some of them are quite new and I would be fascinated to try them (e.g. the Tesla Powerwall), but they can also be more expensive. Depending on the added advantages (e.g. no maintenance, higher power storage), the extra cost may be worth it.

The things we mainly use our power for are the lights in the trailer, our laptops and charging our phones. Sometimes we’ll use a blender or hand mixer, but it’s definitely not every day. We don’t run any of the big power tools during the winter, as the shop isn’t heated and it’s not fun trying to build stuff when your hands are freezing. During the warmer months we do run a miter saw, table saw, electric planer, skill saw, compressor and a few other things. All of those have a big draw when they start up. The miter saw draws between 1100-1200W while it is running, but how long does it take you to make a cut: 5 seconds or less for most things so the energy usage is fairly small per cut.

I can’t say I was an expert going into the whole solar power thing, but I had done some research and I did have some classes on it when I did the Earthship Academy. I knew enough so when I went to talk to the guy at Solar Depot, I wasn’t a complete noob. I’m not an electrician, and I didn’t wire the thing together, but I do have a pretty good grasp on how to monitor it and maintain it.

In the end, if you can figure out what your needs are, do a bit of math, you can figure out what size of system you are going to need. That being said, you could build a system so huge that you could run just about anything. However if the cost of your system is so high that you will never recoup the loss, when compared to being on-grid, then there isn’t much point. If you can cut back on your usage so the cost of your power system is reduced, it can definitely pay for itself within a year or so.

December 2016

Time keeps moving on and it has been a while since my last post. There is a variety of things to cover, so stay tuned.

First, I’ll give you a solar update.

Solar power during winter has its challenges. Optimally, it would be nice to have the batteries in a semi-heated/temperature stable location, but alas, we don’t have such a place so where they are is what we have. That being said, the solar system has been behaving very well. Unfortunately, the weather hasn’t been all that sunny. After that snow we had on my birthday, it warmed up a bit, rained enough to get rid of all of the snow and then it snowed again.

… and again… and again… In fact, there haven’t been too many days in December where it hasn’t snowed at least a few flakes. This means I need to get out and clean off the solar panels each time. I have a system where I don’t need to get on the roof, but it still has its own risks being up on a ladder. I fell from it once and I don’t recommend the experience. Nothing major was broken, fortunately.

The other thing I discovered is it is not sufficient to simply clean off the solar panels. The more you do that, the more the snow builds up at the bottom and then starts covering the bottom panel. Once that happens, your incoming voltage will drop so much that you can’t get enough power out of it to recharge the batteries. So I spent an extended amount of time cleaning off the roof below the panels yesterday.

If the panels are clear of the thick snow, any ice or minor coverage will quickly melt even on a cloudy day. Last Thursday (Dec 15th) was one of the first days where we had any sunshine at all, but it was bitterly cold. I think the windchill that night was down to -32C (-27F). Fortunately, we went back to getting snow and it wasn’t quite so chilly. Today, was a brilliantly awesome sunny day and we were able to get some good power out of it. If it is constantly cloudy, we can go three days or so from 100% battery down to 80% at which point I run the generator to top them up.

I’m sure you’re all wondering where the pictures are so here are some nice scenery shots of the snowy landscape that we now live in.

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In that last picture, on the far right you can see a black barrel beside the smurf house. The snow cap on it is probably 40-50cm (16-20″). As I said above, it’s been snowing a lot. We’ve certainly enjoyed having our driveway ploughing done by someone else, that is for sure.

Kat also managed to sneak a picture of me as I was cleaning snow off the roof yesterday.

cleaningsolarpanels

In case you’re wondering, I have a squeegee attached to the end of one of those telescoping poles you usually use for painting. It works great for the panels, but is less efficient at clearing the roof itself.

While I was outside taking pictures, our bird feeder has been quite the area of activity. Chickadees, bluejays, wood peckers and nuthatches all like to feast on what we have to offer. I managed to snag a picture at just the right time to get a shot of a nuthatch. They are pretty flighty and don’t stay for very long, even less so than a chickadee.

You can see this one on the side of the feeder on the right.

nuthatch

Next, we’ll move inside.

As you may know from previous posts, we have a new bed frame that is working very well. Soon after that was put in, I hooked up this.

led_lightstrip

That’s an LED light strip on a dimmer switch. It’s very snazzy and makes reading in bed very enjoyable.

Once that was in it was time to work on paneling the walls.

This is the area around the closet, before any paint was applied.

bedroompanelling01

This is the first section on the opposite side of the closet, by the window, after the primer was applied.

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Here you can see both sides after the primer.

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Progressing along, all of the window side is now paneled. Some has been painted, some are waiting to be painted.

bedroompanelling04

That last picture is a little out of date, as those unpainted panels now are.

Recently, we were back at my parents for our annual cookie day event. Friends of ours from the Ottawa area, Ian and his wife, Heather, who were attending said event, kindly donated a small set of cupboards to us that they no longer needed. As it turns out, the cupboards fit nicely over the counter where the sink will be going (yes, another project yet to be completed).

Unfortunately, this did mean some adjustments needed to be made to the spice rack we had made to go over the stove, but nothing that we couldn’t handle. But before we could install it, Kat wanted to paint the wall to match the rest of the area. So, she did.

kitchencupboard01

Isn’t that a lovely blue? Anyway, I did need to make a few modifications to the cupboards before I could install them. We don’t have standard wood studs behind our walls, so you can’t just hang it any which way you like. Here is a picture of me on the floor praying to the cupboards.

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It wasn’t a whole lot of work, and we now have a nice new storage location for more things. Actually, all of the spices ended up in the cupboards until I finish making the modifications to the previously mentioned spice rack.

kitchencupboard03

This was right before it got really cold last week, so we haven’t done much since then. I still need to go outside into the truck shelter to do things like make cuts in the pieces of wood we want to use. If it’s -20C (-4F), I’m not really inclined to go out and do that.

Things are winding down now and we’re getting ready for the holidays. We won’t be doing any major traveling this year, just visiting our family and friends within easy driving distance.

Make your holidays great 🙂