Remove Carbon from Existing Building Sector

Technical Approach

See figure 2 in appendix for logic tree for removing carbon emissions from the existing building sector

One aspect of living sustainably involves reducing carbon emissions caused by our existing buildings. However, living sustainably involves many dimensions.  It is important to note that any discussion of carbon reduction in a particular sector must bring in overlaps with other aspects of the economy and of society. Experience has shown that trying to make buildings more sustainable by solving problems in isolation only leads to incremental improvements made at a higher cost.

 If we are to make the required shift to net zero carbon, we must use a systems approach in both understanding the problems and taking action. It appears that many people (not just corporations) will waste resources that are easy to obtain and low in cost. Energy that we use in our buildings is artificially low in cost. To the average person there appear to be no consequence to unlimited use.

 Another factor in increased energy use is a shift away from emphasis on best practice design. In cur practice, typically, the lowest possible first cost rules. This rule applies to both construction cost and professional design fees. These practices began with unethical developers. They have been perpetuated by corporations whose quarterly profits started to define their success. Small businesses and now local, state and federal government agencies have adopted these practices. There are hopeful examples of government agencies that are bucking this shortsighted trend.

 All of our activities should be done with consideration for the long term. Buildings should be designed, renovated, operated and maintained with full life cycle analysis used to make decisions. See the attached Logic Tree for Weaning Existing Buildings from Non-renewable (Fossil & Nuclear) Energy to see the broad web of issues involved.

 Reducing carbon emissions (and resource depletion) caused by existing buildings requires action in the following broad areas (areas for action). Some of these issues are addressed in other chapters. These actions are appropriate to residential, office, commercial, industrial and schools; they apply to all buildings with varying emphasis.

1. Regional planning for reduced transportation need. Transportation systems that are more efficient
2. Decentralized, ecologically appropriate utility systems
3. Reduce paved areas. Use landscape areas for food & energy production
4. Operate buildings in a more resource/energy efficient manner
5. Renovate building envelopes to be climate responsive and resource/energy efficient
6. Renovate support systems to be climate responsive and resource/energy efficient. Support systems include heating, ventilating and air conditioning (HVAC), electrical, lighting, communication network, water, and waste-water.
7. Generate and use carbon neutral energy in resource/energy efficient manner
8. Renovate for increased durability, upgrade for seismic and wind storms, and maintain building for longevity
9. Resource/energy efficient computers, task lighting, equipment and furniture

Operating buildings in a more resource and energy efficient manner is the lowest cost way to begin lowering carbon emissions. To be fully effective this requires the involvement of occupants, maintenance and operational staff. Proper building management support is very important. Each building should have an “energy czar” whose first task should be to come up with a plan for implementation, training and monitoring procedures. This first step applies to all of the areas for action listed above. To be most effective, the energy czar should not be concerned only with energy efficiency but also with comfort, health and productivity.

 A simple way to start lowering building energy use is to encourage people to wear climate appropriate clothing instead of turning up the heat or air conditioning.. People can perform most of the energy efficiency functions of automated control systems such as turning off lights, computer monitors, equipment, HVAC, etc., when not needed. Some functions take more training such as opening and closing windows at the appropriate time to cool and ventilate. Another effective energy-saving strategy is opening and closing existing blinds. Installation of new sunshades and light shelves can produce optimum daylighting and solar heat gain. Turning down ambient lighting and using display and task lighting is also highly effective. Some cash strapped schools are taking this approach and sharing the utility savings with the teacher’s book and supply budgets. Utility savings of up to 25% are not unheard of

 Building envelope renovation can create climate responsiveness and resource/energy efficiency. The specific actions will vary with the building type and use but features such as the following should be evaluated:

• Add operable windows
• Reduce or enlarge glazing areas
•  Change windows to high performance glazing and frames
•  Add solar shading
•  Add appropriate skylights
•  Add roof and wall insulation
• Change to cool roof.

 Look for opportunities to use daylighting, passive heating and cooling and natural ventilation. Plant or prune trees appropriately for shade, daylighting and solar heat gain.

 The design must use the whole building integrated design team process and full life cycle analysis to be effective for the ambitious high performance goals we have established. The items have been artificially separated for the clarity of this paper but they must be designed and operated as an integrated whole to be effective in a synergistic way that leads to cost effective leaps in efficiency.

 Renovate support systems to be climate responsive and resource/energy efficient. Support systems include heating, ventilating and air conditioning (HVAC), electrical, lighting, communication network, water, and waste-water. This may require the full replacement of some of these systems but this is typical for buildings 15 to 20 years old. However, rather than almost thoughtless conventional replacement it is essential to use the whole building process and life cycle analysis described above. Experience has shown that pay back periods will be around eight to ten years for about 30% to 40% energy efficiency savings in excess of current CA Title 24 energy code requirements for new buildings. This will be an energy efficiency improvement of about 50 to 60% for the existing building. To achieve our goal of fossil fuel free buildings we must achieve around 60% to 80% energy efficiency savings in excess of Title 24 (for new buildings) so that the building can be run on a renewable energy.

 Generate and use carbon neutral energy in a resource/energy efficient manner. The renewable energy sources must be selected using full life cycle analysis. Passive collection of solar light/heat, wind and “coolth” is the most effective basis of design. We must design, build and operate our buildings (and live) as if energy is very precious. Photovoltaic (PV) and other renewable electricity generation is a key component because of our dependence on electrical devices. However, HVAC system energy can usually more efficiently use waste heat, cogeneration, renewable bio-diesel 100, renewable ethanol, etc. than PV electricity.

 Renovate for increased durability and fire resistance. Upgrade for seismic and wind storms, and maintain building for longevity. Existing buildings contain large amounts of embodied energy and resources. Therefore, in addition to making them energy efficient, we need to extend their useful life. Generally, articles about environmentally responsible buildings reflect the myth that a business owner or homeowner must buy land out in the country and build a new building to be green. Nothing could be further from the truth. The materials in an existing buildings structure and finishes are resources of the highest value when left in place. New materials embody large quantities of energy and resources.   For example, material acquisition, then processing, transporting, fabricating, and erection of the new construction all result in greenhouse gas emissions. These processes involve energy input and waste at each step. Therefore improving durability and extending the useful life of a building is one of the most important environmental factors to consider.

  Ensure that resource/energy efficient computers, task lighting, equipment and furniture are used in all buildings. The review of components of energy use of an efficient building will show that computers, task lighting, and equipment are very significant users of energy. They must therefore be selected and used with care. Energy Star compliance is only the tip of the iceberg of opportunities.

 Cost and appropriate time frame will vary considerably depending on the quality, function and use of the existing building. Major energy efficiency renovations are best timed to coincide with the need for major support system upgrades, re-roofing, etc. In any case, conventional building needs usually the repairs every 15 to 20 years. Repairs of this nature will not be needed as often when the quality of the building has been brought to the level described earlier.  We should expect to spend up to 30% of the cost of a new building but the benefits, in terms of overall greenhouse gas reduction, will be far greater than just saving on utility bills.