Do we even need electricity?
Humans have lived and survived for thousands of years without electricity. This means in a grid-down scenario we could just go back to the good old, primitive days and live like our ancestors, right? Wrong.
While we are still the same genetically, it would take a lifetime to re-learn all the skills and ways of our ancestors. Even with all that knowledge, it would be a hard and probably rather short life. Oh, and then there is still the coming climate crisis with extreme weather events and adverse conditions.
It is safe to say that self-sufficient power generation is mandatory for everyone who wants to get prepare for climate change.
Solar Power is undoubtedly one of the best sources of power generation. While it’s a good idea to diversify your power sources, solar should be an essential pillar for your climate-resilient homestead!
This article is meant to give beginners an overview of this technology, so let’s take a look into the basics of solar power generation.
What you need to set up a solar power system
Let’s start by taking a look at what you need to get a solar system running.
If you want to install a solar system you obviously need a place to put it. There are different options.
If you have a property you can put your solar panels anywhere using racks. One of the advantages of free-standing solar racks is easy access for installation and maintenance. You are also completely flexible and can choose the ideal orientation and angle for your area.
One of the downsides is that you use up space you could use for other things, like farming or keeping livestock. Depending on the size of your property this can become a big problem.
Another negative is that you have a higher risk of shading through surrounding structures or vegetation. Even partial shading of the panels should be avoided!
By far the most common place to put a solar system is the roof of a house. Most roofs are an unused surface area, so it makes sense to use it for this purpose.
Apart from that, solar panels covering the roofs can serve as additional insulation and keep off some of the summer heat. In newly designed houses, there is also the opportunity of constructing the solar system as part of the roof construction, thus reducing the cost.
Slanting roofs often have a good angle that allows for very good – if not perfect – efficiency. A South-Western or South-Eastern orientation of the roof only diminishes efficiency by about 5%. Even an orientation to the East and West is not too bad, allowing for a performance of around 80% compared to the ideal, Southern orientation.
Flat roofs are not as well suited for solar systems as slanting roofs. The fact that solar panels need to be at an angle means the panels need to be installed in racks. To avoid shading, there must be a certain distance between the rows of racks. This greatly decreases the potential surface area.
That being said, unless the flat roof serves a different important purpose it should be absolutely used for solar!
Another option for installing your solar system is on the façade of a building. This could be an option if you live in an apartment building and don’t have a roof or a garden. Or maybe you already have solar installed on your roof and just need some additional panels for self-sufficiency.
Installation can be a bit tricky and vertical installation is not ideal angle-wise but it’s a lot better than nothing.
What kind of solar panels?
Solar technology is quickly progressing, and better panels drop on the market all the time. For this reason, it’s important to keep an eye out on the latest developments.
Below, I will quickly describe some of the most common types of solar cells that are relevant for us without going too much into detail.
Monocrystal solar cells are grown from a single crystal. This makes them very efficient but also quite expensive. They work very reliably for a long time with low degradation. They are your best choice for your primary solar system on your rooftop or a good rack with no shading.
Polycrystalline cells are not grown but cast from molten silicon. This makes them cheaper than monocrystalline cells but also less efficient. They too are very reliable and are your second-best option if you are on a tight budget.
A completely different category is the so-called thin-film solar cells. In this type of cell, silicon or other materials like cadmium telluride or copper indium gallium selenide (CIGS) is vapor-deposited on a substrate like glass or plastic foil. This allows for flexible designs or even the integration of solar cells in building materials like roof tiles. They are generally easier to produce and thus cheaper than crystalline cells, but also less efficient. In the past few years, thin-film technology has made good progress in that regard, though.
Many different types of material combinations are currently in development, aiming for higher efficiency and longer durability.
One of the main downsides of thin-film cells is a high initial degradation and lower durability which makes them less desirable for long-term, self-sufficient power supply.
Pros and Cons
|Pros||+ High efficiency
+ Less space required
+ Very reliable
+ Very reliable
|+ Usually very cheap
+ Flexible designs
+ Better under bad light conditions
|Cons||– Expensive||– Less efficient
– More space required
|– Usually low efficiency
– High degradation
While the panels are the heart of any self-sufficient solar power system, there are other essential parts you need.
Probably the second most important component for off-grid, self-sufficient power is a good battery. This may come as a surprise to you BUT: the sun doesn’t always shine! Actually, on average, it only shines half of the day. Even less if you consider that there are cloudy days. Crazy, right?
All jokes aside, you are obviously aware that you need some sort of battery for storing surplus power. Ideally, you generate a surplus throughout the day that you store in a battery to use during the night or cloudy days.
The topic of batteries is very complex, though. So complex actually that we are currently working on a blog post just about this topic, so stay tuned and I will put a link here!
Managing the charging of a modern battery requires a separate computer or controller. This controller helps to avoid exhaustive discharge or overloading of the battery and can help prolong the battery’s lifespan.
The inverter is essential to invert the solar panel’s direct current to alternating current. AC is what comes out of the wall socket of your home and is used to run all your electronic devices.
Depending on the design of your solar power system it may be more efficient to use several inverters instead of just one.
How to put it all together
The following graph shows what a basic solar power system could look like.
I hope this short overview of solar power gave you some insight into the basics of this wonderful technology.
In future articles, we will take a more detailed look at the Pros and Cons of different battery technologies, how to calculate the correct size for both the solar modules and battery and can hopefully review some solar power gear that could be useful for preppers, so stay tuned for more!