5 Weather Conditions That Influence a Building's Energy Use

As you work to manage energy costs by paying attention to the systems in your facility, keep in mind that a number of factors beyond your control will affect the amount of energy you use. 

These 5 climatic conditions will influence a building designer’s choice of building orientation, configuration, and envelope, as well as a building’s energy requirements for heating, cooling, and ventilation.

1. Temperature Variations

Daily or seasonal temperature variations will affect the size and selection of mechanical and electrical equipment. Daytime variations are often a result of the topography of a specific building site. For example, a building located at the base of a mountain is likely to have a large range of temperature variations due to different temperature air masses moving up and down the mountainside.

Large variations also occur in desert regions and other areas that have a high percentage of clear skies and sunshine. During the day, the ground heats up from the large quantity of sunlight. At night, this heat is lost because there are few clouds to trap the heat close to the ground.

Solution: These variations provide an opportunity to employ a heating and cooling storage system, such as an active or passive solar heating system, that can reduce energy consumption.

2. Quantity of Sunlight

The amount of sunshine a building receives is another climatic factor that will affect a building’s energy consumption.

Solution: Monthly solar loads must be accurately calculated to determine the quantity of sunlight striking a building during different times of the year. Solar controls include internal or external shading of glazed areas; outdoor cooling ponds; and solar panels. These controls can be used so that a building maximizes the sunlight’s heating capabilities during the winter and minimizes them during the summer.

The color of outside surfaces should also be considered. Use dark colors for absorption on north walls or roofs in cold climates and light colors for reflection on roofs in warm climates.

3. Wind Velocity and Direction

Wind velocity and direction will affect the strategic orientation, configuration, and envelope of a building, as well as its energy consumption. Wind disturbs the film of still air that surrounds and insulates a building, thereby increasing heating and cooling loads. 

Solution: If a building's entrance is exposed to the highest winds, it should be properly shielded from the wind. If not, a combination of high winds and low temperatures during winter months could cause high infiltration, resulting in high energy consumption.

4. Snowfall

The amount of snowfall a building receives is another climatic factor that will affect a building.

Solution: In areas where snowfall is heavy and consistent during winter months, snow cover on the roofs of low-rise buildings can act as a natural insulator for buildings constructed to retain it. In addition, the reflection of ground snow on adjacent low buildings may enhance the illumination level of a building and increase the efficiency of solar collectors, reducing the need for artificial lighting.

5. Building Orientation

The direction a building is facing determines how climatic and topographic factors affect building energy consumption. 

Solution: The orientation affects the power required for lighting systems by influencing the amount of ambient sunlight that may be used for indoor illumination. This affects the building's energy consumption by diminishing or increasing the amount of indoor light, depending on the time of year.

This article is adapted from BOMI International's Energy Management and Controls, part of the SMA® and SMT® designation programs. More information regarding this course is available by calling 1.800.235.2664. Visit BOMI International’s website, www.bomi.org.


Popular posts from this blog

Operating Budgets vs. Capital Budgets for FMs

Don’t Write Off Good Business Writing

Know Your Competition