The transition to clean energy is happening all over the world and it’s growing exponentially. Traditional ways of producing and delivering our energy are not just harming the environment but they are impractical, more vulnerable to failure, and more expensive long term than clean energy. This is not just true on a wider scale when you look at a country or a city, but it is also true on the smallest of scales like your personal energy needs.
Using a house, a boat, or an RV as an example. If you had to run a generator constantly to power your house, boat, or RV; you would have to buy fuel continually, do continuous oil changes and maintenance on the generator. This is expensive, labor intensive, harmful to the environment, and can be a safety factor. If you opted to install a renewable energy system using the sun and the wind you would not only save money long term but would be ensuring that even if you had no fuel or if the generator malfunctioned, you could always have power with no noise, no carbon monoxide, no oil changes, and no maintenance(sustainable). You could still have the generator but only use it as a backup. Many Off-Gridders, already have renewable energy systems also known as micro grids but even if you live in a city and have traditional grid power available, a renewable energy system can work for you.
Depending on the power from the electrical grid which can cost thousands of dollars every year and continues to rise, can leave you vulnerable to system failures due to natural weather-related events like the ones in 2017, when many Caribbean countries lost grid power for several months due to Hurricane Maria. Events that lead to electrical grid failure don’t just happen in the tropics, events like winter storms, earthquakes, fires, computer failures, cyber-attacks, and others can all be responsible for long term grid failures. Hurricane Maria exposed the vulnerability of the old system and there is now a huge shift to independent renewable energy systems not just for homes and businesses but for necessities like traffic lights and street lights.
Strictly from a financial point of view, the money you spend on grid electricity comes out of your pocket every month but in most cases, it is not tax deductible. Contrast this with tax incentives (check your state laws) when you invest in a renewable energy system which do allow for tax deductions on the initial investment. The long-term savings of having a hybrid or fully independent system of energy for your house, boat or RV are generally far greater than the initial investment.
The information on how to design and install a clean energy system is available online and it is not as complicated as some may believe. There are 4 basic components which most renewable energy systems have in common and understanding what each component’s function is will help you in designing and installing your own system
1. solar panel array used to turn sun light into electrical current which is sent to the charge controller(s)
2. Charge controller regulates the amount of DC power from the solar panel array and stores it in the batteries, it also prevents overcharging
3. Battery Bank Several batteries used to store DC (Direct Current) The most common types of batteries are lead acid batteries and AGM batteries (Absorbed Glass Matt. Lithium batteries are far superior in performance and can last 6-8 times longer.
4. Inverter used to turn the DC current from the batteries into AC current to be used on most AC (Alternating Current) household appliances. The inverter can also have a battery charger within the same enclosure to serve as both inverter and battery charger. (see Victron inverter/charger). Some Inverters have Smart features and can take power from the grid directly to the AC appliances when available and automatically switch to the batteries when there is no grid power. The latest models from companies like Victron Energy and Magnum inverters can also automatically start the generator if the batteries are getting depleted.
The size and number of each of these components will vary based on your personal needs. There are two things you can do to calculate your daily consumption of electricity.
If you live in the city, you can read your electric bill to determine how many Kilowatts (1000 Watts) you consume on an average month. (This will help you determine the size of your inverter or inverters as you can stack several inverters to reach your desired Wattage), If you don’t have an electric bill you can calculate by adding the starting Wattage of all your AC appliances and estimate how much time your appliances are ran daily.
Your battery bank size is also a simple calculation. You must have enough Amp hours in your battery bank to power any DC (direct current) electronics you may and to power your AC appliances for a 24-hour period or longer. Keep in mind that you don’t want to discharge your batteries completely and you must leave enough charge in your batteries daily in order to extend your batteries’ life span (50-70% on lead acid batteries) including AGM batteries or (10% on Lithium batteries). The easiest way to calculate your battery size or the amount of AMP Hours you’ll need is to go online and look for a kilowatt to Amps conversion calculator and input your daily kilowatt consumption (used to determine the size of your inverter) and it will give you a rough estimate of the amount of Amp hours that will be used from the batteries. You must then decide the type of batteries you will be using, and this will be the determining factor on how big of a battery bank you will need (Lithium will require a smaller bank because you can discharge the batteries up to 90% without any damage to the batteries, click on the pictures for more on determining the type of battery)
The size of your solar array is determined by the size of your battery bank and the number of Amps you consume daily. You must be able to replenish all your batteries within the peak sunlight hours. If you already figured out how much your daily consumption is then you just have to get enough solar panels to produce your daily consumption during the peak hours (varies on your region of the country but ranges between 4 to 6 hours)
The size of your charge controller is determined by the size of your solar panel array and you battery bank. A simple formula is to take the short circuit current of all the panels and multiply it by the number of panels then multiply by 1.25 (safety factor) and that will give you the size of the charge controller or controllers you will need to regulate the power coming from the solar panels.
Wind generators are another great addition to any renewable system and can supply a good amount of power at night when the solar panels have stopped producing power. Wind turbines are very commonly used on boats and land applications.