Inverters are a critical part of any photovoltaic system, and especially so in RV solar panel systems. Electricity comes in two flavors, AC and DC.  AC is alternating current, and the vast majority of electrical systems in the US and Canada utilize alternating current. DC is direct current, and is also what is used to charge a battery, and it can be the output from a battery.  Photocells from a solar panel generate their electricity in Direct Current. Therefore, to make that electricity useful in a RV, residential, or commercial setting, you need to convert the electricity into Alternating Current.

Inverters turn Direct Current into Alternating Current. Between your batteries and your devices you will generally have an inverter.  An inverter is NOT a surge suppressor or power conditioner. To protect against sudden surges in your power, a proper grounding system must be in place. As part of your yearly service for your RV, make sure that your mechanic knows to double check the grounding system in your RV, and to replace any corroded or diminished connections or conductors.

Solar Panels are a natural fit with an electrical system that is intended to run off batteries. Your Recreational Vehicle is such a system! Since solar panels generate DC, and your battery requires DC to charge, no invertor is needed between the batteries and the solar panels, but an inverter will be necessary though between the the battery and the rest of the electrical system to run your appliances.

Technical Aspects of Inverters

Inverters use solid state electronics to rapidly change the direction the current is flowing. First one direction, then the other. In the US and Canada, 60 hertz is the standard. That means the direction the current is flowing must change directions sixty times in one second.

In a typical AC system, the output of current makes a clean sine wave, steadily increasing to peak, and next then decreasing to the down peak. The output from the solid state electronics is a square wave. While this will run some electrical devices, higher end electronics find this type of power quite unacceptable. Fortunately, inverters come in many flavors.

The higher end inverters produce a clean and even sine wave. When purchasing the inverter, or contemplating an upgrade to your current inverter, it is important not to go with the cheapest model you can find. Spend some time, and find one that will meet the needs of your electronics, and you will save money in the long run.

Advantages of the modern inverter

Originally, inverters used mechanical means to accomplish the inversion from DC to AC. These devices were quite noisy, since there was a physical object switching the current sixty times per second. Luckily, today’s solid state devices are electronically enabled and so they are silent.

The other advantage of the newer inverters is easier maintenance. Quite often when an inverter goes bad, the problem can be narrowed down to one circuit board, and that board can be replaced. Inverters typically come with a 1 to 5 year warranty, so make sure you go with a trusted brand.

Inverter efficiency is a key component.  If you take the output wattage, and divide it by the input wattage, you will find a percentage that correlates to the efficiency.  High end inverters will have an efficiency rating of over 90%.  Some power will always be lost due to heat, keeping inverters from ever reaching 100% efficiency.

Installation

Inverters and other system components should be located as close together as possible.  This eliminates long conductors and minimizes power loss from voltage drops.

TIP: Inverter installation is governed by NEC article 690, “Solar Photovoltaic Systems.”  Most companies provide literature for code compliant installation in their manuals.

As always, if you have any questions or concerns about inverter installation, I urge you to contact a licensed electrician with your questions.  Feel free to use the ‘contact me’ button located at the top of the screen, and I will attempt to answer any questions you may have.

What is overcurrent protection?  Overcurrent protection is fuses and circuit breakers typically.  They are installed between the solar panels and the batteries, and between the batteries and what you are running off of the batteries.  They are also your first line of defense against fire.  Between proper wire sizes (which I will cover in another article) and overcurrent protection, you can sleep sound at night knowing you’ve done what you can to prevent an electrical fire.

In a PV (photo voltaic) system, it is critical to protect the solar panels from accidental back-feeds which may occur during operation. The way a PV system works is quite simple. Solar panels charge batteries that you then use for power in your RV. If power were to start flowing from the battery to the solar cell, or if a current spike were to occur damage can happen to the equipment, costing you time and money to repair them.

Photo voltaic system, or PV system is the technical name for a solar panel installation.  It includes every piece of equipment that is included in the installation of your solar panel install.  The industry standard is to refer to an entire system as a PV system.  When purchasing items, or dealing with an electrician, they will understand you much better if you use the proper terminology.  Beware of people who do not know this who are trying to sell you something!

Nearly all photo-voltaic system circuits require over current protection, including PV source circuits coming from the solar panels, the inverter (if used), and any battery or load circuits. In laymens terms, this means that lines coming from the solar panels to the battery must have overcurrent protection, and lines coming out of the batteries must have overcurrent protection.

The National Electrical Code, or NEC, was established for your protection. In Canada, they have something very similar in the CSA’s CEC. Both standards were implemented to protect people from the possibility of fire caused by an electrical system. Therefore, compliance with these codes is not only strongly recommended, but can be a real life saver!

Additional overcurrent protection can be placed closer to the equipment being used.  Special surge protectors can be used in RVs to protect your computer equipment or other devices.  In bathrooms, or where there is water close by, use ground-fault interrupters to protect individuals from accidental shock or electrocution.  These devices do not replace the main overcurrent protection, but instead augment it.

Accessibility – All overcurrent protection devices, whether they are fuses or circuit breakers, must be readily accessible. Where you mount the box that houses these devices must have clearance in front of it for at least three feet, and must not be blocked by large objects. If you spend a few moments planning your installation, you should be able to install a fuse box, or a breaker box, that is easy to access, and will not detract from your home on the road.

How a Fuse Works – During an overcurrent situation, the amperage draw becomes excessive. This excess amperage causes the conductors and devices to become hot. In a fuse, this heat causes the ‘fusable link’ to actually burn up. Thus a fuse cannot be reset, but must be replaced. Never bypass a fuse with a piece of conductor, and never replace a fuse with a different type of fuse. Always keep spare fuses on hand.

How a Circuit Breaker Works – A circuit breaker uses the same concepts as a fuse, but instead of a fusable link burning up, the heat will cause the circuit breaker to ‘open’ up. The advantages of circuit breakers is that they can be reset after they trip. Also, a circuit breaker can be used as a means to disconnect power from a leg or system so you can safely work on them. If a circuit breaker trips too many times, their performance will be degraded. Replace them if this occurs.

When installing an electrical system, if you have any doubts or concerns, please contact a licensed electrician. If you have any questions, feel free to post them here, and I will try to answer them for you.  

In simple terms, solar panels work by collecting photons from the sun and converting them into DC (Direct Current) electrical power. The sun’s rays energize electrons in the panels strongly enough to get them active and moving around.  From that point, power is then channeled through an inverter, which transforms it into a basic voltage and AC power.  (AC, or Alternating Current, is more efficiently transferred along electrical wiring and is the standard in appliances, cars, RVs, houses, and industry-in-general).

Solar panels will work even in cloudy conditions since the sun continues to give off enough diffuse light to be absorbed, however they may not work at full capability. During winter months, the shorter days will also cause a reduction in electrical generation, and a snow-covered roof will stop production completely. Regardless of how often your panels draw the sun’s energy, you will need to immediately use it or divert it to a battery as the strip itself cannot store power.

how do solar panels work. image from solarpanelswattage.net

While solar is an excellent choice for alternative energy, it is not a simple plug-and-go technology. You may install the panels yourself, but if you are not completely comfortable with the process then it is best to hire a professional.  As previously mentioned, wiring and batteries are essential.  In some communities it is possible to feed your excess electricity back into your power company’s grid, and get paid for it instead of storing it in your own  battery.  This is important to know because battery technology has not kept pace with the progress in solar cell technology, and so you will create more electricity than you can store — in an RV that means that it is best to use your appliances during daylight hours for maximum return on your system.  Of course, there will be plenty of energy on your battery at night for modest use, like using your lights and computer as they don’t use as much power — you might think twice about using a hair-drier or microwave though.

(On houses, most companies recommend installing solar panels when your roof is being built or re-shingled. This will reduce or eliminate the possibility of water leakage around the posts. It is also far easier to install them when you are able to locate the rafters quickly, which is nearly impossible on a covered roof.)

Overall, the benefits of solar energy outweigh the investment of money and time. Even though they take some effort to install, the yearly maintenance is almost non-existent. You will also be doing your part to eliminate pollutants and cut greenhouse gases, all while saving your wallet too.

Anyone who has ever had a flat car battery knows how infuriating and time consuming it can be. If you have to buy a replacement or catch a cab, the experience is expensive as well as inconvenient. A solar car battery charger is a simple and inexpensive device that helps to keep a battery fully charged, and so has the potential to save hundreds of dollars and many hours of frustration.

Solar panels contain photovoltaic cells that convert the energy from sunlight into usable electricity. Use of this type of energy is encouraged by governments and environmental groups all over the world. One of the advantages of solar power is its low cost: sunshine is free and panels require little maintenance. Appliances and machinery that are powered by solar energy operate independently of any electricity network, and it can be used in isolated regions where connection to a grid is not possible. In the longer term, widespread use of sunlight to generate power for residential and commercial buildings is hoped to bring about a significant reduction in environmental pollution caused by burning fossil fuel.

solar car battery charger. image from solargadgetsinfo.com

Solar car battery chargers are small panels that sit on an automobile dashboard. When plugged into the cigarette lighter or connected directly to the battery, the panel converts energy from the sun’s rays into electrical current. The trickle of current produced when sunshine falls on the panel is sufficient to keep the battery’s level of charge topped up. This type of device is especially convenient for maintaining charge in the batteries of vehicles and boats that are not in constant use.

Many solar chargers for car batteries have LED indicators to show when they are operating. Panels that are more sophisticated have an overcharge prevention function that turns the device off when a fully charged state is reached. If you want to avoid being let down by a flat battery, purchasing an environmentally friendly charger could be a very shrewd investment.

The cost of solar panels depends upon a number of elements. Not only does it depend upon where you get your panels, it will depend upon whether you make the system yourself and how many panels you need to take care of your power needs. Once you figure the financial costs of the system, you will also see many other advantages of clean energy that should figure into the overall costs of using solar power.

In many cases, the cost of solar panels can be as much as $40,000 for a single family home. However, you have to consider that there are many ways to cut down this price. For instance, if you are a do it yourselfer, you can save by building and installing your own solar panel system, which is a large portion of the costs. You may also consider any local, state and federal tax incentives you can get with using an alternative energy source.

cost of solar panels drops every year. image from inhabitat.com

If you are in a region that gets a good amount of sunshine during the day and year, you can end up taking in more energy than you use. You may then sell this back to the utility company that can help alleviate the costs. Furthermore, learning to use less energy so that you do not need as many panels in the first place not only saves you money but also helps you become a better conserver in the long run.

You should also consider the positive environmental factors when you think of the advantages of clean energy. You are using a source that does not harm the environment and essentially produces free energy after the initial investment. Also, solar panels typically require very little maintenance and can last at least 30 years providing reliable power to your home or other living space.

While solar powered fuel is a relatively new energy source, it is quickly becoming one of the most important energy sources in the world. Typical homes operate off of oil and fossil fuels to good, power lighting, and power appliances. If you are researching the benefits of turning your residence into a solar power home you will quickly discover the advantages are vast. Understand the advantages of green energy and reduce the carbon footprint you put on the environment.

Unlike oil, power fueled by the sun is renewable. While the sun does not emit rays during the night or during severe storms, it will return in full force. In today’s modern society everyone in the country is dependent on oil and fossil fuels to life day to day. With reserves in danger of being depleted, it is time to consider a realistic and safe alternative.

solar power for home. image from kollewin.com

Power fueled by the sun is non-polluting. Unlike oil fuel sources, solar power does not emit greenhouse gases into the environment. Scientists have proven that gas emissions are causing a warming affect on Earth. Not only is solar energy renewable, it is also sustainable.

Statistics show that the United States consumes more than 90 percent of the world’s energy on an annual basis. The remainder of the world uses just under 7 percent. If you understand the affect that fossil fuels and gas emissions are having on the planet and living ecosystems it is time to take a proactive step towards change. Sunlight constantly hits the earth in large amounts throughout daylight hours. This sunlight can be absorbed and turned into clean green energy with the right solar cells. For very little money out-of-pocket you can turn your dependent home into an efficient home. Not only will you lower your monthly expenses you will also take part in saving the environment.

Rising utility bills have consumers searching for cost-effective alternatives. Air conditioning was once considered the best man-made inventions. However, many people are burdened with astronomical utility bills due to the high-energy use of air conditioning units. There is no question many alternative energy sources are good for the environment. Many consumers are more concerned with the low-cost advantages of alternative energy.

One of the most economical and environmentally friendly energy sources is the sun. You will notice that solar lights are available in home improvement and discount stores. The high demand for solar power is decreasing the cost of solar lights and solar panels. Many consumers save money each month by using inexpensive solar lights around the exterior of their homes.

100 watt solar panel. image from: solarpanelsglobal.com

You can buy an inexpensive 100-watt solar panel that is easily installed. As more consumers are discovering the affordability of a 100 watt solar panel, the prices are improving. The panels will reduce your utility bills. Most home improvement stores carry a wide variety of solar panels. Installation is easy and you will be able to install the panels on your own. However, you can to hire a professional.

If you are ready to save money on your utility bills, you will want to consider installing solar panels. Many people have discovered the advantages of alternative energy and are virtually off the grid.

If you live in an area of the country with an abundance of sun light, you will benefit great by installing solar panels. You can buy one panel and as your utility costs decline, you can put the money you save toward another panel.

The major advantages of alternative energy are most alternatives sources are far less expensive. Sun light is free. You just need a method of converting the sun light to useable energy. Solar panels are affordable and you will be amazed how easily the panels are installed.

Solar energy is one of the best renewable resources our earth has. Green energy is a field that is quickly growing as more people learn about how easy it is to use as well as the benefits of using it. Using solar cells to heat or generate power for your home is smart and easy to achieve.

There are solar cells for sale from many companies in many of the major metropolitan areas today. Solar energy is effective and easy to use. First the panels are placed on your roof and connected to your house. Next the panels gather sunlight and convert it into electricity. Finally you remain connected to the typical electric grid and can actually sell back power to the power company.

Solar cells for sale, image courtesy of quadmodsusa.com

Another great part about installing solar panels on your home is that much of the cost can be covered through state and federal clean energy programs. These programs are set up to encourage people to invest in clean energy for their homes. Taking advantage of these programs are simple. First you find out the cost of installing the panels and connecting them to your home. Next research the programs and find out what they need to help you. Usually it will be a quote or the receipts for the parts you have installed. Then they return the money to you or pay for the remainder.

Solar energy requires a large investment up front, but the benefits and programs that you can take advantage of greatly help reduce the cost. The additional benefits of generating all of your own power for free and potentially even selling some back to the power companies guarantees you will earn back your initial investment in record time. Green energy is the future of energy and by acting now you can remain ahead of the pack and be the first to use green energy.

It only takes about one hour to construct a homemade solar cell, and the necessary materials are readily available. Although this type of homemade solar cells does not produce enough power to be practical, making one can be a fun project. This can easily be done by following these step-by-step instructions.

1. Obtain a half square foot of copper flashing, a clear plastic CD or jewel case, hot glue, table salt, two pieces of insulated copper wire, and soldering equipment.

2. Cut a small strip from one end of the flashing and set it aside.

3. Place the larger piece of flashing on a stove burner and heat it on a high setting until it develops a thick black coating. This should take about half an hour.

4. Turn off the burner and allow the flashing to slowly cool.

5. After about 20 minutes, remove the copper from the burner and lightly scrub off any remaining black coating. Some small black spots will remain. Do not scrub too hard, or the layer needed for the cell to work will be damaged.

5. Solder a wire to each piece of copper. Cover the soldering with glue for insulation.

6. Glue both pieces of copper to the inside of the CD case, but make sure the two pieces are not touching.

7. Apply glue all around the edges of the inside of the case to act as a seal, leaving only one small opening on one edge. Make sure the wires stick out so that their free ends are exposed.

8. Close the CD case and make sure all glued edges are sealed. Pour salt water in through the opening. Fill it until the copper is almost completely covered.

9. Seal the opening and wait for the glue to dry completely.

home made solar cell, image courtesy of sci-toys.com

Follow these instructions to make a homemade solar cell. Although it would take thousands of these homemade solar cells to construct enough solar panels to power a house, this can be a fun and worthwhile project.

Below is the list of solar energy power facts I compiled from different sources

- There are systems which use solar energy for heating and not just generating electricity
- One square meter of solar panels saves about $0.06 per sun hour.
- One square meter of surface receives the same amount of heat from the sun as 0.07 gallons of oil fuel gives out in burning.
- Solar panel system costs about $50,000 to install if you want to cover 100% of house electricity consumption
- Solar system costs around $2,000 to cover 100% of house heating
- You have to face your panels south if you live in the north hemisphere and north if you live in a south hemisphere

- Fossil fuels is a preserved sun energy, since they consist mainly from dead plants which use sun’s energy to grow.
- Leonardo Da Vinci designed one of the first solar concentrators in attempt to use solar energy for industrial purposes
- In just one hour more sun’s energy falls on Earth that entire population uses in a year
- Third world countries today is the largest growing market for solar energy, because many of those countries are located in areas with a lot of sunlight and they use way less energy than citizens in developed countries.
- Cost for solar generated electricity constantly falls unlike the one generated by fossil fuels
- Atmosphere and clouds absorb and reflect about one third of the Sun’s energy which reaches the Earth
- Modern day solar panels convert only about 15-20% of sunlight to electricity, the rest is wasted, thus if 1 kWh of sun energy falling on a solr panel it will only generate about 150 watts per hour
- Japan consumes about half of all produced solar panels
- Germany generated 6,200 GWh of solar electricity in 2009 and it gets about 1.1% of it’s total electricity consumption from solar power plants
- Largest solar power plant is located in Mojave Desert in North America, it consists of solar reflectors which cover the area of 4 square kilometers
- Around 2 billion people around the world don’t have access to electricity

Let me know if you know more of solar energy power facts which deserve to be included in this list. I did not put any stats about the Sun, the surface and core temperature, size and distance from Earth, because I don’t think it’s really relevant to solar generated power which this site is about.