Good temperature control is vital for a productive high tunnel greenhouse, and this in turn means that the ventilation system needs to be effective and efficient. Regardless of whether a grower uses fans or “natural ventilation,” it is important to make sure that the system is designed properly and working well. Here are a few pointers that will help you improve your system.
The concept of cooling a greenhouse with thermal buoyancy and wind goes back to the …
Milk must be cooled from 98 degrees F. (37 degrees C.) to storage temperature, typically about 38 degrees F., to preserve its quality. The cooling process involves removing 56 BTUs of energy from each pound of milk (27 kilojoule per kg). Typically, a refrigeration system does this by using a special refrigerant fluid to remove heat from the milk and “reject” the heat (usually) into the outside air.
The basic refrigeration …
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| Photo: eXtension Ag Energy. |
Agricultural producers use heated water for a variety of jobs, including general cleaning of structures, equipment, livestock, poultry, fruit, and vegetables and to sterilize equipment. Dairy farms use especially large quantities of hot water daily for both cleaning structures and equipment and for processing milk products.
Although electrical water heating is not uncommon, most agricultural producers use propane (LP) or natural gas because of their higher efficiency. In addition to gas and electric water heaters, agricultural …
The operating condition of tractors and other farm machinery can affect the fuel efficiency of those machines; therefore, maintenance is crucial for energy and financial savings.
Tractor engines and engines in self-propelled equipment should be maintained in good condition. It is possible for a tractor to be operating below peak performance without noticeably affecting field performance. Preventive maintenance and scheduled tune-ups are recommended to insure that the engine operates efficiently. Follow the recommendations in the operator’s …
Jatropha seed oil is used in soaps, and energy for lighting and heating in subtropical and tropical areas where it is planted as living fences to stop soil erosion. Its biodiesel potential is being researched because the seeds contain from 25% to 40% oil.
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| Jatropha fruits and seed. Copyright FAO, UN |
Jatropha curcas is an oilseed tree or shrub that grows in …
Wood is an attractive alternative fuel for greenhouse heating – it is renewable, locally produced, and usually less expensive than other fuels. While wood is not for everyone, an increasing number of growers are turning to it as an economical heating alternative for their facilities. Fuel wood, waste wood and biomass are all potential sources of heat …
Combustion of biomass used to heat greenhouses.
Fire, or combustion of biomass, is arguably the oldest known and most widely used controllable energy source on earth. In recent years, rising costs of fossil fuels and the development of advanced equipment have made biomass combustion an economical, efficient, and practical energy source.
Combustion is familiar to all of us, but many do not realize that it is essentially a chemical reaction. In the process of combustion, two ingredients …
Thought about growing a biomass crop for combustion fuel on your farm? This article offers three questions farmers can ask to evaluate growing energy producing combustion crops. It examines wood, woody crops and grasses in more detail.
Find these topics and many other related Farm Energy media resources at the Farm Energy Media archive.
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| Switchgrass briquettes a combustion fuel. Photo: Daniel Ciolkosz, Extension Associate, Penn State. |
Unprocessed biomass comes in a variety of sizes, shapes and other properties, ranging from a gooey puddle of microscopic algae to the massive trunk of a large oak tree. If any feedstock is to be used effectively for combustion, it usually needs some form of processing to ensure that it is suitable for effective use in combustion equipment. The most common types …
