Business

More EV charging stations amp up home values

As electric vehicles continues to speed ahead in the market, a new study from the University of Maryland's Center for Global Sustainability (CGS) found that homebuyers are willing to pay a premium in areas where it's easy ...

Energy & Green Tech

Study proposes profitable ways to repurpose industrial waste

There is money to be made—and potential to reduce greenhouse gas emissions—by finding a second life for the potato peels, fried dough particles, cheese whey and other industrial food-processing waste products that routinely ...

Energy & Green Tech

Targeted policies could help decarbonize Canada one home at a time

Be it through the food we eat, vehicle we use or way we live, we use fossil fuels and emit greenhouse gases in various activities in our daily lives. We need to reduce emissions across sectors, starting with our homes. This ...

Energy & Green Tech

Energy Sec. Granholm brings clean energy gospel to CES show

Anyone wondering what compelled the U.S. Department of Energy's first-ever appearance this year at the CES tech show—traditionally an annual showcase for consumer gadgets—need only consider what its boss sees as her main ...

Engineering

We need to learn to live with less steel, says researcher

Steel is one of the most important materials in the world, integral to the cars we drive, the buildings we inhabit, and the infrastructure that allows us to travel from place to place. Steel is also responsible for 7% of ...

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Greenhouse

A greenhouse (also called a glasshouse) is a building in which plants are grown. These structures range in size from small sheds to very large buildings. A miniature greenhouse is known as a cold frame.

A greenhouse is a structure with different types of covering materials, such as a glass or plastic roof and frequently glass or plastic walls; it heats up because incoming visible solar radiation (for which the glass is transparent) from the sun is absorbed by plants, soil, and other things inside the building. Air warmed by the heat from hot interior surfaces is retained in the building by the roof and wall. In addition, the warmed structures and plants inside the greenhouse re-radiate some of their thermal energy in the infra-red, to which glass is partly opaque, so some of this energy is also trapped inside the glasshouse. However, this latter process is a minor player compared with the former (convective) process. Thus, the primary heating mechanism of a greenhouse is convection. This can be demonstrated by opening a small window near the roof of a greenhouse: the temperature drops considerably. This principle is the basis of the autovent automatic cooling system. Thus, the glass used for a greenhouse works as a barrier to air flow, and its effect is to trap energy within the greenhouse. The air that is warmed near the ground is prevented from rising indefinitely and flowing away.

Although there is some heat loss due to thermal conduction through the glass and other building materials, there is a net increase in energy (and therefore temperature) inside the greenhouse.

Greenhouses can be divided into glass greenhouses and plastic greenhouses. Plastics mostly used are PEfilm and multiwall sheet in PC or PMMA. Commercial glass greenhouses are often high tech production facilities for vegetables or flowers. The glass greenhouses are filled with equipment like screening installations, heating, cooling, lighting and may be automatically controlled by a computer.

This text uses material from Wikipedia, licensed under CC BY-SA