Farming and other primary activities can account for a significant portion of pollution in our environments. This can be from cattle producing greenhouse gasses (methane) all the way to nitrate and phosphorous run off into our water systems that can lead to algae blooms.
Making our farms green is not only the responsible thing to do but it makes economical sense also. Fossil fuels are becoming increasingly expensive and as sources of fossil fuels become scarcer, they will only become more expensive. This has shifted our conversation about energy to renewable sources. Though traditionally we would speak about green (clean) sources of energy, there are still plenty of other renewable sources of energy that we can use for our farms. If you are interested in those conversations, make sure to look at my article on biomass.
Common Renewable Energy Sources (RES) For Farms
Common renewable energy sources include:
- Solar radiation (solar energy)
- Wind energy (wind power)
- Energy of rivers and streams (hydropower)
- Wave energy
- Geothermal energy
- Dissipated thermal energy: heat of air, water, oceans, seas and reservoirs
Sources Of Renewable Energy
- The sun
- The Earth
Renewable Energy Sources Groups For Farms
- Non-traditional renewable energy sources of the 1st group (NRIE-1), which includes: energy of the sun, wind, geothermal energy, etc.;
- Non-traditional renewable sources of the 2nd group (NRIE-2), which includes biomass, products of its processing, household waste, etc.
The concept of “Non-conventional renewable energy sources (NRES) does not include renewable energy sources obtained from large hydropower plants (hydroelectric power plants of large capacity), in contrast to hydropower used from small rivers and watercourses.
Solar Energy For Farms
The energy of the sun is the most promising source of electricity that can replace and even displace traditional fossil energy sources from the market, fully covering the world’s electricity needs in the future. You can get this energy without stopping anywhere in the world, and completely free of charge, while the behavior of the sun is much more predictable meteorologically than the movement of air masses that create wind.
Global solar energy market
In 2014, for the first time in history, it became more profitable to invest in renewable energy projects, rather than traditional fuel, as the growth rates of these industries were equal, according to Bloomberg New Energy Finance. Global investment in new solar power plants from 2010 to 2019, inclusive, amounted to $1.3 trillion.
Equalized cost of electricity (a metric that compares different methods of generating electricity) decreased by 81% for solar PV generation from 2009 to 2019. Solar power has caught up with coal in Germany, Australia, the United States, Spain and Italy. Solar power is expected to be cheaper than coal in China, Mexico, the United Kingdom and Brazil by 2021.
The future of solar energy in the world
Solar generation is expected to increase from less than 1% of total global electricity production in the 2010s to over 10% (cumulatively over 1,800 GW of capacity) by 2030. By 2050, 22% of electricity will be generated by solar power plants.
It is expected that in the future it is solar energy that will grow the fastest of the renewable energy sources: in the next 20 years, the total revenue from this industry is expected to reach $5 trillion. Companies around the world are investing $5.3 trillion in solar energy by 2050.
The cost of producing energy from converted sunlight has been steadily declining and will likely continue this trend, while the cost of energy derived from burning fossil fuels will rise, due to less use and environmental costs. Solar energy production costs will drop another 66% by 2040.
Solar energy technology
The sun’s rays are concentrated and converted into other useful forms of energy using various technologies. Today there are several such technologies and they are constantly being improved. The main ones are concentration (solar thermal) technologies – CSP and photovoltaic technologies – PV.
The number of installed floating solar power plants increased more than 100 times in 2014-2018 and reached 1 GW in September 2018. Most of these energy facilities were introduced in Asia, but gradually this technology is spreading to Europe as well.
The technology of dual use of land is gaining popularity in agricultural crops – solar power plants are located directly above farm fields in Japan, Italy, France and Germany. Before installing installations, researchers carefully calculate the features of the fall of the shadow and the risks of its negative impact on the growth and development of plants, and the size of the yield.
Supports for solar panels are made without the use of concrete, which makes it possible to quickly dismantle structures if necessary. Technologies for the use of solar energy in agriculture in hot southern countries (Cyprus, Turkey, Greece, Egypt) are especially interesting, since low shading in combination with the modernization of hydraulic engineering should have a beneficial effect on the volume of products grown.
The use of solar energy in agriculture
Solar agribusiness technologies address a wide range of agricultural challenges. The presence of available land and a significant area of roofs and walls of houses and outbuildings allows you to receive and accumulate large amounts of electricity through solar sources.
The installation of photovoltaic systems is carried out to generate electricity, which can be used to operate pumps, an electric shepherd in pastures, honey extractors in an apiary, electric knives and other equipment, as well as to provide electricity to residential buildings. You would well and truly be living off of the land.
Air collectors are used for heating and ventilation of premises, creating a comfortable living environment for people, farm animals and maintaining the temperature and humidity at a given level. This is something we talked about a lot when talking about making sure your piggery is set up properly.
Greenhouses equipped with solar panels not only retain heat and accumulate it, retaining it inside, but also provide the micro-climate necessary for plants that may not grow in your native climate.
The use of devices for heating and ventilation in grain and vegetable stores, in warehouses allows you to do without the continuous participation of service personnel in maintaining the specified parameters of the environment and to preserve crops, buildings and equipment in the best possible way.
Reducing costs with solar panels
Solar collectors and S-WALL systems manufactured by Solar Fox for personal households and industrial enterprises are designed to solve the problems of heating and ventilation in objects of any capacity. Installation of installations is quick and does not require permits from the state supervisory authorities; they can easily be included in existing engineering systems and equipped with sensors if necessary.
All work on the production and assembly of solar panels is carried out by employees of the developer company without the involvement of contractors unfamiliar with the specifics of the equipment. Air collectors are equipped with a modern safety system that prevents short circuits or fires.
Solar ventilation and heating systems reduce costs with a payback period of 12 months to three years. This is of course dependent on how much sun you get in your local area. A vineyard in Italy will get a lot more sunshine than a sheep farm in the highlands of Scotland!
Wind Power For Farms
Wind energy can significantly reduce the dependence of the world economy on oil, gas, uranium and other types of fossil fuels in a relatively short time, as well as significantly reduce the emission of greenhouse gases into the atmosphere, which have a detrimental effect on the climate of our planet. According to NREL, the generation of 1 MW of wind energy prevents the emission of approximately 2,600 tons of carbon dioxide.
Offshore wind farm
According to IRENA, the world’s installed wind power capacity has grown from 92.5 GW in 2007 to about 467 GW in 2016, including 453 GW of onshore wind generation facilities. In the same year, the industry employed 1.2 million people directly and indirectly, with half of these jobs in Asia.
According to the IEA’s Tracking Clean Energy Progress report on global renewable energy, wind generated 16% of the world’s renewable energy in 2017.
Wind investment rose 3% in 2018 to $128.6 billion, with the offshore wind segment hitting record numbers for the second consecutive year.
Currently, Denmark, Spain, Portugal, Sweden and Germany are the leaders in the field of wind energy (per capita). Though Scotland is making huge strides in this direction. I knew that wind would come in handy some day!
Prospects for wind energy in the world
In 2018-2050, the number of wind power in the world will increase 6 times. By 2050, 26% of electricity will be generated by wind farms.
Companies around the world will be investing $4.2 trillion in wind energy by 2050. The price for this energy will drop by more than 40% by 2030, making this type of energy one of the cheapest and very advantageous for island nations and farms located on the coasts.
Wind energy technologies
When building a wind farm, the main costs go to the purchase of equipment and the installation of turbine generators, after which the operating costs of maintaining its operation are minimal.
A wind turbine can operate at wind speeds in the range of 13-90 km/h. The noise generated by the wind turbine meets the WHO (World Health Organization) guidelines for residential areas.
Turbine technologies: onshore and offshore wind farms
Wind farms can be built both on land (onshore), and at shallow depths in the shelf zone of the seas (coastal or shelf, offshore), where strong enough winds often blow. In addition to the standard offshore wind turbines with a rigid base dug into the seafloor, a new type of offshore wind turbine is being developed, placed on floating platforms, anchored to the seabed by anchor cables.
In 2018, most of the wind power equipment (57%) was produced by four market-leading companies – Danish Vestas, China’s Goldwind, America’s GE Renewable Energy and Spain’s Siemens Gamesa.
Aerial wind farms
Efforts continue to improve the idea of generating energy from wind power and to minimize the cost of generating renewable energy. Many inventors and startups around the world are working on this.
Netherlands-based Ampyx Power is proposing a gradual transition from wind turbine construction to second-generation wind power systems, the Airborne Wind Energy System (AWES), which consists of a drone tethered to a generator of electricity on the ground. The English Kite Power Systems proposes to extract wind energy from air systems based on a kite, a similar system is being developed and tested by the Google X Makani project.
History of wind energy
The idea of generating electricity using the power of the wind is attributed to the German physicist Albert Betz. He is also considered to be the developer of wind turbine technology. The first wind turbine was built in Vermont in the 1940s. The first water-type wind farm (offshore) Vindeby was built in 1991 off the coast of Denmark by the joint efforts of the Danish company DONG (now DONG Energy) and the German Siemens.
Geothermal energy
Just like hydraulic, wind or solar resources, geothermal energy sources are clean, safe and renewable. “Geothermal” is a word of Greek origin and consists of the roots “warmth of the earth”. Geothermal, therefore, is called the energy that is contained under the outer shell of our planet in the form of heat. So far, we have not learned to convert all heat into electricity, but only that which is concentrated in special areas where molten masses of magma are very close to the surface. Essentially vents!
Maibarara Geothermal Power Plant Geothermal resources located at an accessible depth in natural reservoirs in the form of steam or high temperature water (most often rainwater) are heated by flowing through constantly hot rock areas. Certain landscapes, such underground sources of hot water and steam can turn into geysers, hot springs and lagoons when they come to the surface.
Global geothermal energy market
Geothermal energy facilities are already in operation and are under construction in various parts of the world, including countries such as Russia, Iceland, Italy, the United States, Chile, Peru, El Salvador, the Philippines and Indonesia.
Investments in geothermal energy in the world increased in 2020 by 10% to $ 1.8 billion. Geothermal energy will likely not be possible for the majority of farms today but as technology develops, this may become more feasible. Not only as an energy source but also as a source of heat. Advantageous for those cold winters.
History of geothermal energy
One of the pioneers and leaders in this segment is Italy and, in particular, Enel Green Power. Back in 1904, the Italian prince Pietro Ginori Conti conducted experiments in Tuscany to transform steam energy into electricity. In 1913, the world’s first geothermal power plant was opened in Larderello, and in 2013 it celebrated its 100th anniversary.
The history of geothermal energy in Russia begins in the mid-50s of the last century, when a group of scientists was first organized to study the geothermal potential of Kamchatka, as a result of which the first Pauzhetskaya geothermal power plant in the USSR was built.
Development stages and operating principles of a geothermal project
The development of a geothermal energy project consists of several phases. First, with the help of special underground samples, the place where the geothermal reservoir is supposed to be located is determined. The next phase is deep exploration; if geoscientific tests confirm that the location is correct, wells are drilled and a power plant is built on the surface, or steam is redirected through pipes towards an existing station.
Drilling up to 5 km deep is economically justified. The deep drilling phase is also accompanied by environmental studies to best position the well and optimize steam production.
The steam is transported from the wells to the power plant using insulated steel steam pipes. In a power plant, steam enters the turbine and rotates it, and an electric generator attached to the turbine generates electricity. After passing through the turbine, the steam is cooled in a condenser and converted into water. Part of the water obtained in this way is returned to an underground natural reservoir using special re-injection shafts, the other part is released into the atmosphere.
When the temperature of the geothermal source is low (120-170°C), binary cycle technology is often used. In such systems, the geothermal fluid is used to vaporize another liquid with a lower boiling point than water through a heat exchanger, and then immediately sent to the reverse injection system, thereby completely replenishing the natural reservoir.
Tidal Offshore Power Plants
The principle of operation of underwater power plants, generating electricity from the force of the ebb and flow of the tides, is similar to how wind farms work: at the bottom, turbine generators are installed, the blades of which rotate underwater currents arising from the ebb and flow of the water.
Such turbines are much smaller than wind turbines (they are about 15 meters high, with a rotor about 18 meters in diameter), since the density of water exceeds the density of air by 800 times. This means that a current of 5 knots (about 9.25 km/h) has the same strength as a wind of 350 km/h. Lots of energy potential! There is no reason why this could not be done a smaller scale with your local rivers and lakes for farms. Once costs are more reasonable.
Since the movements of the ebb and flow are related to the phases of the moon and are well predictable, the amount of energy that an underwater turbine can generate is more stable and much easier to estimate than in the case of wind power. Besides predictability, offshore turbine generators have another advantage: they are hidden from view. Among the disadvantages compared to wind power are the higher costs of installation and operation, as well as the potential threat to the operation of the power plant for underwater flora and fauna.
The 398 MW MeyGen project under construction in Scotland is the world’s largest sub-sea power plant project as of spring 2017, and the only industrial scale tidal project in the world to begin construction.
Thermal Tidal Power Plants
There are several commercial power plant projects in the world that receive electricity using Ocean Thermal Energy Conversion (OTEC) closed or open cycle technology. This technology is being developed and tested, for example, by the Energy Island research group.
Temperature conversion technology involves extracting energy from the difference in water temperatures at the surface and in the depths of the ocean. To generate electricity, a difference of at least 20 degrees Celsius is required, so equatorial waters are ideal for such projects, especially in places where great depths are available close to the coast and polar currents flow at the bottom, for example, in the Philippines.
The advantage of this technology is that such power plants are able to produce electricity stably throughout the year.
Potable water is a by-product of open-type thermal conversion. Warm seawater is placed in an evaporation chamber to remove salt and produce steam, which drives a heat turbine, which in turn generates electricity. The water is then condensed in a chamber cooled by seawater pumped from deep within the ocean.
In a closed-type temperature conversion system, warm seawater is used to heat an auxiliary fluid such as ammonia, which boils at a low temperature and creates steam that drives a heat turbine to generate electricity. The auxiliary liquid is then cooled with cold water from the deep ocean, condensed and can be reused. A never ending source of energy as long as it is kept in equilibrium.