3 Greenhouse Heating Tips You Can't Ignore
Greenhouses can provide great environments for growth because the materials normally used (such as plastic and glass )are very effective in allowing heat and light to enter as well as allowing heat to escape. However, one major problem is that they can overheat during the day if there is no control. Because they lack insulation, they can actually hit freezing points at night because they are unable to retain their heat. Here are three greenhouse heating tips that you cannot ignore.
The real challenge lies in being able to control the swings in temperature. Conventional wisdom does this by using energy to generate heating or cooling systems as and when they are needed. However, it would be much smarter and far more sustainable if you were able to use the excess solar energy during the day time by storing it, so that it could be used at night. You may also be able to install heating and cooling systems which are economic and run on renewable fuel. One good way of tackling the problem is to minimize your energy requirements.
1.) Use thermal mass for storing solar energy:
A good way to even out the temperature variations in your greenhouse is to use thermal mass (also called a heat sink). Thermal mass refers to any material with the capacity of storing thermal energy (though some materials are much more efficient than others). For example, water stores about twice as much heat as concrete and up to four times as much as soil.
Using thermal mass achieves twin objectives. Because it absorbs energy during the day, it has the effect of cooling. However, at night, the drop in temperature causes the thermal mass to release energy and thus provide heating. The most common thermal mass implementation is to use barrels full of water because of the storage capacity. They should be stacked in direct sunshine.
2.) Heat exchangers:
You can add a heat exchanger to the thermal mass for the circulation of air. The system goes by many names, such as Climate Battery or Subterranean Heating and Cooling System, and operates on the same mechanism. During the daytime, warm humid air is pumped into an underground system of pipes. The drop in temperature forces vapor to condense and release energy, which is stored in the soil. At night, because of the drop in temperature, heat is extracted and circulated with the use of a fan. The process is simple and well tested.
Renewable energy heaters:
In addition to solar energy, you may require additional heating. You should look at heaters that operate on economical and renewable fuel. A commonly used heater is called a Rocket Mass Heater, which is an extremely efficient form of a wood burning stove. The heater circulates hot air through a layer of brick or stone before it is expelled from the exhaust and the heat is stored and released gradually over a period of time. They normally use chambers capable of double combustion, which burn wood far more efficiently than the normal wooden stove.
*Image courtesy Flickr creative commons.