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Why Energy Management?The Need for Green
Believing in global warming -man-made or not- or even global cooling doesn’t matter where building automation comes into play in reducing the energy usage of green buildings. There is another issue we're all painfully aware of: It's worth taking a few minutes to understand why and how of the evolution of fuel because this will affect design decisions made for buildings that will stand for decades. This diagram represent the sources and consumption of petroleum per day: Take a note of the figure for Motor Gasoline: 9.29 million barrels per day (the chart here does not include diesel because fuel oil has multiple uses). One process converts 10,000 cubic feet of natural gas to one barrel of fuel. To meet the gasoline consumption in 2007 requires 30 trillion cubic feet of natural gas. Now we have plenty of natural gas but... Replacing gasoline alone requires more natural gas than we have today and would leave us nothing for commercial buildings. What about alternative sources? There is also the issue of radioactive waste, a problem created in 1977 when the re-processing of spent fuel to create more fuel (energy) and much less waste in breeder reactors was banned because the result contained Plutonium-239, which is used in nuclear weapons. France, which is very dependent on nuclear power uses, uses extensive recycling of fuels to produce less waste. Permitting, planning and construction also takes many years which tends to turn investors away, especially when environmental lawsuits can delay the process further or halt it entirely. What about renewable sources? The “on-demand” sources are useful and have no fuel costs, assuming that the biomass systems are fueled with what would otherwise be waste materials, whether production byproducts or municipal waste. And you can draw on these as needed, assuming you have a sufficient supply of the source of the energy. Outside of biomass, though, these are limited by geological factors.
This chart shows the mix of electrical generation in 2007. It should be evident that unless more coal and nuclear plants are built, increasing demand for natural gas can only lead to higher prices. Our buildings will have to become more energy-efficient. Within the life of the buildings built today, we are likely to see a major change in our energy mix. We are either going to need to find other sources of energy, particularly electricity, for our buildings to make up the loss, or be prepared to conserve more. Original ASHRAE Standard 90-1975 goal: Reduce energy usage by 40% We have been here before, starting with the oil crisis of the early 70s. And yet, thanks to the relatively cheap energy we enjoyed only a third or so of US commercial building floor space today is not covered by even the simplest energy-saving strategies offered by a building automation system. And even where better energy efficiencies were sought, things still fall short Inefficiencies continue But that’s about to change Greening to standards
ASHRAE Advanced Energy Design Guides
US Green Building Council LEED* Standards
Mandates for “green” or “sustainable” buildings are increasing. The Energy Policy Act of 2005 committed new federal buildings to meet ASHRAE Standard 90.1-2004. Many cities are adopting their own requirements, written into code. The descendant of the original ASHRAE Standard 90-1975—90.1-2007—lays out standards for energy-efficient buildings, but also takes into account indoor air quality which was not considered when 90-1975 was drafted. Subsequent versions for greater efficiencies will roll out over the years. A higher-performance standard, 189, is in development. ASHRAE is also developing a series of Advanced Energy Design Guides, currently for 30% more efficiency than Standard 90.1-1999.
The US Green Building Council has been developing and updating its LEED standards. The 2009 versions, more harmonized than prior versions, have been through two public reviews in 2008. This is not the complete set of standards; there are more currently in development. Certain prerequisites must be met in order to claim points in each of the rating categories in a LEED standard; they must also be met to earn enough points to reach LEED certification. In reviewing these standards for aspects in which a building automation system has an effect, we broke them down into these rough categories. Please note that these are our internal designations; they do not appear in the standards themselves. The traditional HVAC control system earns very few points by itself; the same is true for lighting control systems. But when you start expanding the system with additional capabilities and additional applications, the number of available points grows dramatically—almost tenfold. Synergies and advantages of a combined system
Now most of the applications noted could be achieved with independent systems but there are advantages to combining them, as noted here. And what could be more “green” than reduced costs? Greening beyond LEED:
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The bad news is, there are problems with every single one of them. We have plenty of coal, but concerns over global warming make it very hard to get new plants built. Nuclear is not as unthinkable as it once was, especially with newer safer technologies such as pebble-bed reactors, but the specter of Chernobyl is regularly raised when nuclear is suggested.
The “as-available” sources are in substantial development these days, but a big issue is their intermittency: we simply do not have substantial energy storage systems. Solar, though, has the advantage of being available during the day when the need is greatest – but one wonders at the effect when a significant percentage of the grid is powered by photovoltaics and a regional-sized snowstorm comes in.