Wondering the difference between solar and photovoltaic? Is it the same thing?
As a whole there is a difference between solar and photovoltaic. Solar can be any form of collected energy from the sun which includes, thermal energy transfer. This could be used to heat water or a thermal mass like concrete. Photovoltaic is the process of converting electricity from sunlight.
The two types can be confusing so read on to get a better understanding.
1.The Difference Between Solar and Photovoltaic Or PV
In general, the formal meaning is the generation of electric current when two substances are exposed to light. In this case we were talking about sunlight or sunlight energy.The difference is noted between two semi conductors known as the photovoltaic effect. These protons then release into electrons which converts into electricity.
This process takes place in what we know as photovoltaic cells or a solar cell.The cells are combined to add up a desirable voltage connected in the form of series or parallel. These cell are then protected by glass and heated into place. Usually surrounded by a frame or in other words a solar panel.
2. The Difference Between Solar And Photovoltaic Vs Thermal
There are different types of solar that you can purchase. Photovoltaic is a form of solar. Solar Panels convert sunlight energy into electricity. Other types of solar or thermal solar. Thermal solar collects the energy from sunlight to heat either water or air. Solar thermal can heat evacuated solar tubes to increase water temperature for things like hot water or swimming pools or even heat.
Thermal solar for air just simply hits the circulating air inside of the solar equipment to collect heat. The same principle applies for solar air as it would in your attic. When the sun lays on your roof all day your attic heat up. The heat mass is then transferred to another source for use. To sum is up if you had a fan in your attic. You extract it to your basement you could use that heat as a supplement to your regular heating system.
3.Is Solar Thermal Better Than PV?
Thermal solar is better than solar PV. Thermal solar can be 65 to 70% efficient. Which means out of 100% it can convert 70% of that into energy. As solar PV the highest rated solar PV panel is only around 20%. This means it can only convert 20% out of 100% of the sun lights energy into electricity.
You’re far better off to go with thermal solar however thermal solar often results in more maintenance. Running fluid or liquid through the system to be heated they can always be a risk of leaks. This is a common issue with older thermal solar systems. They can become very costly to fix usually resulting in there expire.
They can also overheat and dissipate pressure in the form of blow offs. This can cause more problems in the system design. When used in colder climates they must be filled with glycol instead of water. This is so they do not freeze up in the middle of winter. It can happen on a colder day when we get snow that covers the tubes and prevents them from heating up.
4. The Difference Between A Solar Cell and Solar Panel
A solar cell is one single cell in entire solar panel. The front side of the cell is usually negative and the backside is positive. The voltage differential usually results in about a half a volt. The solar cells are strung together in series to form a solar panel.
Different configurations of solar panels equal different voltages so that more cells are required to reach the desired effect. Once solar cells are hooked and series to add up to the desired voltage the amperage usually stays the sum of each cell.
However some parallel series configurations can be done to add up and purchase within side the solar panel. The end result will be a positive and a negative terminal in which the voltage is collected to be terminated into an electrical system.
5. What is Thermal Solar Exactly?
Thermal solar is the collection of solar energy from the sun. The solar energy is collected through a thermal collector. This collector is usually reflective to absorb as much energy from the sun that it can. Thermal solar usually contains water or glycol to be heated with inside the thermal solar collector. It is then transferred or circulated usually to a heat exchanger that’s added to some other source of heating equipment.
In simple terms imagine water being circulated up on your roof through the solar collector. This superheats that water circulating through your furnace to help with your furnace or some other heating source.
The result is lower heating bills or less burning of natural gas or fossil fuels.
6. Solar PV VS Solar Thermal?
There are many factors that play solar PV against solar thermal. Solar PV is usually more expensive to install upfront but less maintenance. Combine with government grants or energy efficiency programs this can make solar PV more feasible.
Solar pv can be worth it if you do your research first before you make your purchase. Be aware that there are a number of solar contractors that will sell you on production numbers alone. These production numbers can be a bit skewed or a false statement.
Unfortunately there is no true way to prove that you have been sold a 10000 watt solar system that only produces 7000 watts instead of the sold number. It is such a gray area the sales or install in which you bought the system from would just blame it on the weather.
Solar thermal is usually less upfront cost but usually results in maintenance overtime. As mentioned above running through or running water through thermo solar can result in leaks. This can result in more maintenance. However solar thermal will give you the most bang for your buck in the short term in the most energy production. The energy production is well worth the cost.
7. Which Technology Is More Cost Effective?
The most cost effective to install would be thermal solar as you can do a solar hot water system for around $5,000 complete turnkey. To get the same energy output from a solar PV system you need to spend $30,000.
But remember solar thermal has more maintenance so depending on how much maintenance you need to do this completely into the overall factor.
Solar thermal can also be used for larger applications like in floor heating. These applications can greatly help you reduce on your energy savings for heating.
8. Other Types Of Solar Collectors?
Other types of solar collectors or solar parabolic collectors. They reflect and concentrate the sun’s energy to one spot almost like a magnifying glass. The concentrated solar array super heats the point of concentration into a gas or liquid which can be heated to the point of steam to turn a generator.
This generator can produce electricity. Smaller systems of this nature are not really feasible as they have not become mainstream on the market. They tend to take up a lot of space and can be cumbersome.
However much larger systems can be feasible for power production. The reason for this is the parabolic collector needs to follow the exact angle of the sun all day long. This means that the parabolic collector needs to move which means more mechanical parts and more maintenance. Several motors will move the solar parabolic collector to follow the sun all day long to make sure that concentrated point of energy is focused.
9.Which Has More Maintenance ?
Parabolic solar would have the most maintenance. There are many moving parts to keep this rolling smoothly. This is why it’s not feasible in smaller systems for the every average day home. Thermal solar would be next in line as it would have maintenance with any leaks or circulating systems that could fail.
Solar PV or photovoltaic would be the third in line as you have a little maintenance but still could have issues with the panels for falling trees or branches and keeping the panels clean. The electrical can also fail. Thermal solar air would be your least amount of maintenance as the systems usually work on natural convection with very minimum or a little moving components.
10. Solar Thermal Energy For Heat
Solar thermal energy can be used for heating. This is a very passive form of heat, is it will not give you a complete heat but it can definitely help out reach the setpoint of the desired temperature. This can either be solar thermal circulated water or solar thermal air collection.
Most times it will not get up to temperature that is required for heating a floor however it can assist greatly. You can incorporate this one, building a new home to help heat and floor or reduce heating costs.
The solar heating can be a supplement to your regular heat. Often referred to as passive solar. It can also be a hot water assist which seems to be the most popular. It can help heat a hot water tank or pre heat the cold water going into the tank. This results in a closer set point for the hot water to reach temperature. Also it will result in less fuel or electricity being used to reach the final set point of 140 degrees fahrenheit.
Other types of passive solar is to make sure you build your home in a south facing direction with the proper thermal pane windows. Positioned right this can drastically reduce energy costs in the winter. It would be climate specific though as you would not want this in a warmer area. It would defeat the purpose and cost you more in air conditioning in the summer months to stay cool.
11. Solar Air Collectors How Do They Work?
A solar air collector is a device that converts the sun’s heat or energy into heat that is more concentrated. Much like a black surface attracted heat this works on the same principle. Usually a large collector set on a roof or some other area exposed to the sun is constructed.
The construction is made up of an enclosure, usually painted black inside. On the collector side there is usually glass or plexiglass so the sun can penetrate it. Inside the collector is a series of air channels designed to collect the heat from the bottom and rise to the top. As we all know heat rises.
In addition there is usually an intensifier installed inside the unit like black painted aluminum as it has a quick transfer rate of heat. At the bottom of the solar collector and the top are vents which are hooked to an air circulator to collect the heat and bring it indoors to be used. This process is usually done with some for od solar powered circulation fan. Combined with a thermostat to tell the fan to turn on and off from the set point inside the solar collector.
Although these type of solar collectors are inefficient, they are very cost effective to construct and come with very little maintenance as there is not much to break. Except for a fan maybe. They are more for use in the should heat season like spring and fall. They are not much good in the dead of winter months.
We hope that this article gives you some for of understanding of the difference between solar and photovoltaic as well as the other types that are being used on the market today. Solar energy is not going anywhere and has been around for years. The technology keeps improving and the cost keeps coming down.
Many areas in the world are ahead of North America with their solar technology and usage. They day is not far off from seeing solar on everyone’s rooftop to supplement their power usage.