Solar Power is the conversion of energy from sunlight into electricity primarily from photovoltaic panels and to a lesser extent from concentrating solar power plants, where thousands of mirrors focus on a receiver to convert sunlight into heat that drives a steam turbine. Solar panels were initially used only as a source of electricity for small electronic devices, but lately solar energy has become a major source of electricity for homes and industrial buildings. A solar power system is a basic independent solar installation designed to generate electricity for domestic or industrial use, meeting basic needs such as lighting, TV, notebook, refrigerator, ceiling fan and water pump in rural areas. The solar power system can be coupled with the local power grid or it can be installed 100% off-grid using a battery power system.
The grid system is designed for rural areas where public grid utility is missing. Excess power generated during the day is used to recharge the battery that will supply electricity during the night.
The grid connected or grid tied system is always connected to the public grid utility through the inverter that converts the dc current, generated by the panels, into alternating current at 110 – 220 V for use in your home. Excess power generated during the day will be sold back to the utility for a credit to be used during the night when sunlight is not available. It is the right choice if you have a stable and reliable electricity network but want to save on your energy bill.
Grid-tied system with battery backup is the right choice if your national grid is unreliable and outages are not uncommon. During the day your home will use the energy generated by the solar panels and the excess energy will recharge a small battery that will become an emergency power source during blackouts. During the night you will use the energy from the grid and only in the event of a grid blackout, the controller will switch to off-grid mode absorbing the energy stored in the battery to power your home.
How to Calculate Solar Panel, Battery and Inverter
An ordinary appartment uses 2500 W. During the day the solar panels can totally supply energetic consume of an appartment. The battery will supply the electricity in the night and thanks to the inverter will be transformed from 24V to 110 or 220V for house equipment uses. The solar power system includes:
Photovoltaic solar panels (8 modules) to generate electricity
Mounting rack to easily install panels on the roof or in the garden
Solar charger – controller
Energy storage battery
Inverter woth output of 110 V / 220 V ac and 50 / 60 Hz automatic tracking main frequency
Please note, the standard home design is for 2500 W power according to following terms: the power output is calculated on areas with daily average peak power sunshine of 5 hour, and the battery set capacity is designed for power storage of 10 hours output in saving energy configuration of your home.
During the day:
The 8 solar panels produce 2500 W. If you use less energy, you can store the excedence in the battery. If you have only conditioner turn on, maybe 1.000 W, solar panels supply air conditioner and you put 1500 W in the battery. For 10 hours of sun, you can put 15000 W in the battery.
During the night:
To know how much electricity you consume, add all electrical equipments power (W) and multiply by the hours that are turn on. TV is 200 W for 3 hour per night = 600 W
Radio is 20 W for 2 hour per night = 40 W
Light is 100 W for 4 hour per night = 400 W Conditioner is 1000 W per 5 hour per night = 5000 W
Total power for 1 night is 6040 W The battery must supply minimum 6040 W during the night, it means teorically 6.040 / 48V = 125 Ah. Because of battery efficiency is 75%, we use a battery size 48V – 150 Ah.
How Solar Panels Works
A solar power plant is a great way to power your home with clean, renewable energy and cut your electricity bill. The photovoltaic system consists of a few photovoltaic modules connected in series, arrays. It is modular, high flexibility in power, easy transport, quick installation. The photovoltaic cell is the main component of the panel and converts light into electricity. During the day the cell absorbs photons (part of the sunlight particles that contain energy) and the silicon atom releases an electron (negative part of the atom) leaving a positive hole. The cell is made by putting an artificial junction layer, p / n layer, which keep the released electron and the positive hole separate, generating electricity when we create an electrical circuit between the front and back of the layer. With this external circuit the released electrons can return to the positively charged holes. The electrical power extracted from a cell is proportional to the intensity of the sunlight. The efficiency of solar cells when converting sunlight into electricity is 20% of solar thermal energy.
Solar Photovoltaic Panels Specifications
High efficiency A class. Diod by-pass glass with cells in EVA (etilene vinil acetato) covered by waterproof film. Connections by plug MC4. Certifications: ISO 9001, CE, TUV IEC 61215 e IEC 61730.
Solar Controller & Inverter
The Inverter is the brain of the solar system and converts DC electricity to AC electricity for your home uses. The inverter is always coupled with a controller that monitors the utility grid and controls the solar system production.
Orientation of Solar Photovoltaic Panels
Here are many considerations to do about the orientation of Solar Panels including site shading, site conditions, different climatic circumstances, installation costs and aesthetics. The rigth orientation will produce the most amount of energy production per year, but many systems can take into consideration for example an existing roof and will be installed in a non pefect orientations, with only a small reduction in total output. The first rule is to never install a solar system that faces in any portion of the 180 degree arc of the compass that faces north, or in the shade of a building or a tree even if the new solar microinverters allow solar panels to operate independently of each other, and if one or two modules end up in the shade of a building, the others will produce electricity.
Advantages of Renewable Energy
The economy growth of any country presently is based on fossil fuels such as oil, gas, coal and conventional electric generation plants are based on their combustion. But the great demand of energy from emerging countries coupled with air pollution and the problem that fossil fuels are non renewable energy (dwindling resources), persuade Governments look for alternative fuels and innovative choices to promote a more sustainable development. The term Green Power is used for electricity generated from alternative sources such as wind, solar, biomass. The increase of green power plants, displacing conventional plants, will reduce air pollution. Most of renewable energy sources such as solar, hydroelectric, and wind are pollution free and will never run out. Solar energy can be directly used for heating and lighting buildings, or indirectly for heating water and for producing electricity. Anyone can install a small renewable energy plant at home, reducing electricity bills and increasing power reliability. Furthermore, the excess of green power generated can be sold to the electric grid provider.
While traditional sources of energy will continue to be a critical part of energy markets for the future, energy from renewable sources has become an increasingly vital part of power generation. Lower cost of new technologies, environmental and energy security concerns have created great demand for alternative energy. Alternative energy sources have become multi billion dollar global markets attracting new investors. The incentive to use 100% renewable energy, for electricity and transport has been motivated also by global warming. The most developed nations round the world already have renewable energy contributing more than 20% of energy supply, allowing us to maintain our quality of life while avoiding catastrophic climate change. The main critics of the 100% renewable energy are about the variable output of solar and wind power.
We all currently rely heavily on coal and oil for our energy. But fossil fuel is a non renewable energy, and it will become too expensive or too environmentally damaging to retrieve. To replace fossil fuel energy, in many applications, we can start using renewable energy sources such as solar and wind energy that are pollution free and will never run out. Talking about renewable energy, the most important source is the sun. Sunlight can be used directly for heating water, for lighting buildings, for generating electricity.
The sun is an inexhaustible and extremely powerful source of energy. Solar technologies use the sun’s energy to provide heat, light, hot water, and electricity. To take advantage of the sun, several solar energy technologies have been developed during the years:
- Solar Hot Water: Producing hot water with solar energy.
- Solar Electricity: Using the sun’s heat to produce electricity mostly by steam and turbine.
- Photovoltaic Systems: Producing electricity from sunlight by photovoltaic panels.
- Solar Daylighting: Using solar energy to light buildings.
Human Beings have been harnessing the wind’s energy for years. A modern wind turbine uses the wind’s energy to turn a shaft coupled with a generator to make electricity. In a windmill the shaft was coupled with a pump for water or with a press for grinding grain in the past, and in some areas of the planet are still used. A wind turbine is built with a three blades fan mounted on a 40 meters or more tower to take advantage of more wind’s energy. In case of wind, blades work like airplane wings. The difference of pressure between upside and downside of the wing, given by shape of wing, pulls the blade toward low pressure zone, causing the rotor to turn. Usually many wind turbines are built close each other to form a wind plant and connected to a utility power grid. Stand alone wind turbines are only used in farmers to cut the electric bill. Wind is one of the fastest growing source of renewable energy. New high resistance materials and technology improvements (tower should be structurally stable to minimize vibration and well protected against corrosion from environment), allow wind plants to be a profitalbe and sustainable business. We provide a complete range of services for mini and medium utility scale wind projects. Here is the basic steps to do before installing a wind plant:
- Find potential sites: to identify suitable terrain, start analyzing topographic maps, availability of the land, presence of existing roads and buildings, natural parks, etc.
- Verify with local authorities all the permits required to build wind towers plant.
- Evaluation of wind force of the site: general information of the wind resource can be obtain from National Weather Service Stations, Universities and air quality monitoring.
- Monitorize the site for at least 1 year, to evaluate the wind resource in all seasons.
- Make a simulation of several wind direction to determine the best location of each wind tower. The exact estimation of energy production will reduce investment risks.
Hydroelectricity is the term referring to electricity generated by hydropower. The production of electrical power through the use of the gravitational force of falling or flowing water. The basic hydroelectric power plant is built with a dam on a river to store water that will be released to spin a turbine coupled with a generator to produce electricity. Hydroelectricity is produced in 150 countries, with the Asia generating 30% of global hydropower. China is the largest hydroelectricity producer, with the 22.000 MW generated by Three Gorges Dam, the largest hydroelectric power station in the world. The cost of hydroelectricity is very low, compared to other renewable sources, making it a competitive source of renewable electricity. The cost of electricity from a hydroplant is in USD 5 cents per Kw/hour. Hydropower is a very good source also for its flexibility, plants can be ramped up and down to adapt to changing energy demands. The hydroelectric plant produces no direct waste, and has no output of toxic gas.
Geothermal energy is thermal energy generated and stored in the Earth. The geothermal energy of the Earth’s crust originates from the original formation of the planet (20%) and from radioactive decay of minerals (80%). The difference in temperature between the core of the Planet Earth and its surface, drives a continuous conduction of heat from the core to the surface. Temperature at the core mantle boundary reaches 4.000°C (7.200°F). Rock and water is heated in the crust at over 300°C. Geothermal energy has been used for bathing and for heating since ancient Roman times, but it is now better used to generate electricity, desalination and agricultural applications. Geothermal energy is reliable, sustainable, environmentally friendly, attractive cost, but has been limited to areas near tectonic plate boundaries. New technologies have expanded the areas of the Planet. There are many geothermal reservoirs of hot water that can be drilled into underground reservoirs for the generation of electricity. Some geothermal power plants use the steam from a reservoir to power a turbine/generator, while others use the hot water to boil a working fluid that vaporizes and then turns a turbine.
- Geothermal Electricity Generation: Producing electricity from the earth’s heat.
- Geothermal Direct Use: Producing heat from hot water within the earth.
- IGeothermal Heat Pumps: Using the shallow ground to heat and cool buildings.
Bioenergy is the energy that comes from organic matter. Human Beings have used bioenergy for thousands of years, ever since started burning wood to cook food. Although we presently have many sources of biomass, such as vegetables, residues from agriculture, the organic component of municipal wastes, wood is still today our first biomass energy source. The large use of biomass energy will cut gas emissions in the atmosphere.
- Biofuels: Converting biomass into liquid fuels.
- Biopower: Burning directly biomass to generate electricity, or converting it into gas or oil fuel.
- Bioproducts: Converting biomass into chemical products that usually are made from petroleum.
Disadvantages of Fossil Fuels
Fossil fuel is the primary non renewable source and it is the remains of the decomposition of plants and animals lived thousands year ago. There are 3 types of fossil fuels: coal, petroleum, and natural gas. The energy development of fossil fuels in the 18th and 19th Century set the stage for the Industrial Revolution, and nowadays, 80% of the world’s energy needs is from fossil sources. The heat given by burning fossil fuel can be used directly for heating or for electric power generation, or can be converted to mechanical energy for vehicles. Fossil fuels are non renewable, unsustainable resources, which will eventually decline in production and become exhausted. The combustion of fossil fuels leads to the release of pollution into the atmosphere. The fossil fuels are based on organic carbon compounds. Because the combustion with oxygen coal plant produces carbon dioxide, sulfur dioxide, small airborne particles, nitrogen oxides, carbon monoxide, hydrocarbons, volatile organic compounds, mercury, arsenic, lead, cadmium, other heavy metals.
Energy Industry is focused on making available old and new energy sources to meet the needs of modern society by mixing the production of conventional and renewable sources of energy, and recovering energy that would otherwise be wasted. Energy efficiency can have benefits to society with changes in economic costs and changes in the environmental effects. Contemporary industrial societies use primary and secondary energy for transportation, for industrial uses and for domestic utilization such as lighting, heating, air conditioning. The old energy industry comprises coal industry, oil industry, gas industry, and atomic power industry. The new energy industry is focused on the renewable energy industry, including alternative and sustainable manufacture, distribution, and sale of biofuels. In order to mitigate climate change, all efforts are to develop sources of alternative and renewable energy. An energy source is the element that provides the energy by conversion from another energy form. The nuclear fusion in the sun is the most important energy source for the Planet Earth (it is in the form of radiation). The natural elements we found in nature, wind, water, solar, wood, coal, oil can be converted into usable energy and are resources to produce heating, lighting, and many other uses.
Non renewable energy sources come from energy limited sources, they are exhaustible and include: fossil fuels as petroleum, gas, coal.
Renewable energy is the energy source practically limitless reserves: solar, wind, geothermal, waterfall (hydraulic flows).
As stated by Mr. Lavoisier, “nothing is created”, the energy production is a transformation of the forms of energy. For example, the kinetic energy of a movement can be converted thanks to a dynamo, into electrical energy. Electrical energy can be used for lighting, and for heating (thermal energy). Energy production usually requires an investment in money and energy. Drilling for oil or building a wind power plant requires energy. The fossil fuel resources that are left are often increasingly difficult to extract and convert. They can require higher energy investments. If investment is greater than the energy produced, than the resource cannot be an effective energy source.