Studying utility bills covering at least one year, or more, is a good start and it acts as the base line… – MEP MiddleEast

Deep energy retrofit can be defined as an energy conservation measure in an existing building, leading to overall improvement in the performance of the building.

It is a whole-building analysis and construction process that aims at achieving on-site energy use minimisation in a building by 50% or more, compared to the baseline energy use calculated through the analysis of utility bills, by making use of latest technologies, materials and good construction practices.

Deep energy retrofit also involves remodelling the building to achieve harmony in energy, indoor air quality, durability, and thermal comfort. An integrated project delivery method is recommended for a deep energy retrofit project.

Deep Retrofit is the significant upgrade of building towards the near zero energy requirement, which is practically feasible and achievable.

By going for deep energy retrofit we can create most value out of investments in the long-term because of the saving potential.

Conventional energy retrofits focus on isolated system upgrades (lighting and HVAC equipment, pumps and motors, ventilation system etc).

These retrofits are generally simple and fast, but they often miss opportunity for saving more energy cost effectively.

Deep energy retrofits require a systems-thinking approach rather than the traditional approach followed for a conventional retrofit.

A systems thinking approach is evaluating the interaction between different isolated components in the building.

For example, Home Performance with Energy Star offers a comprehensive, whole-house approach to improving your homes energy efficiency, comfort and safety while helping to reduce the energy costs by 15%-20%.

In addition to the efficiency measures taken for a building, a deep energy retrofit requires occupants proactive role in energy conservation to understand energy uses in the home, as well as the activities of the occupants.

Most retrofit approaches are considered light because they focus only on upgrading lighting equipment and adding new motors to the heating and cooling systems.

This leaves out bigger savings stemming from deeper measures, like new windows, which can reduce heating and cooling loads to the point where big-dollar value equipments can be reduced in size and cost.

Such interventions are typically not considered because of high up-front cost and perceived higher risk. Those implementing a deep energy retrofit consider all major capital needed in the building over the next several years and plan interventions to this business-as-usual scenario to create higher efficiencies.

Deep energy retrofit can significantly reduce household energy consumption by taking into consideration space heating and cooling, hot water, lighting, appliances and electric loads as part of retrofit.

Studying the utility bills covering at least one year, and preferably more, is a good start and it acts as the base line.

Blower-door testing, Infra-Red imaging and duct-blaster testing offer valuable information about current energy consumption pattern. An assessment of existing conditions of the building envelope is also important.

A deep energy retrofit probably will include changes to the entire building envelope as well as heating and cooling equipment. Moisture must also be carefully managed by adding perimeter drains in the basement.

Exhaust fans in the kitchen and bathroom, or a whole-house ventilation system, where those features are lacking, play critical roles too. Both the site and the structure should be examined with an eye toward adding rooftop- or ground-mounted solar-energy installations, solar hot water collectors, or a wind turbine.

With a sharp reduction in heating and cooling loads it might be possible to downsize or even eliminate some heating and cooling equipment.

Most of the living spaces will be involved in retrofitting, so its important to minimise the disruption by starting from the outside of the house and then moving inside.

Approaching the project from outside also makes it easier to keep the insulation and air barrier continuous. If air leaks in at the bottom of the house, it leaks out at the top, which makes the house cold and drafty in winter.

A poorly insulated roof can also make a house hot in summer. Insulate the slab and walls and provide air sealing.

Replace doors and windows with energy-efficient joinery, and specify glazing based on the houses exposure to the sun. Old windows are like big holes in the walls and often leak both air and water while functioning poorly.

Properly installed, Energy Star (or better) windows seal the holes in the walls to keep out water and weather extremes.

Filling empty wall cavities with cellulose is a cheap, easy, effective way to warm up an old house.

Blowing cellulose into existing wall cavities is an art. In fact, there are now inexpensive ways to check with Infra-Red cameras to make sure that all voids have been filled without disturbing the existing plaster or sheathing on outside walls.

Use high-efficiency mechanical equipment and heat pumps where possible with appropriate controls. Also, provide proper ventilation for combustion equipment.

Replacing window air conditioners/split units, with a central system wherever possible can also save energy right away, as long as the ductwork has been placed in the conditioned space.

Reconfigure plumbing to distribute hot water efficiently with proper insulation of water pipes, and choose a high-efficiency water heater.

All the sanitary wares and fixtures should be chosen as per the Energy Conservation and Building Code guidelines. Use low flow fixtures as far as possible.

Increase natural daylighting wherever it is possible. Install energy-efficient lighting systems and controls. Replace CFL with LED lights of same the luminosity.

Fixtures, appliances, and lighting once you have reduced space conditioning and water-heating loads, the lighting, appliance, and plug load is the next big-ticket energy item.

A new Energy Star refrigerator will use 15% less energy than a standard model. Replacing old light fixtures with LED fixtures helps to lower electricity bills by up to 25%-30%.

Once your energy consumption has been reduced significantly, it becomes reasonable to produce energy at site with systems such as photovoltaics, wind power, hybrid system(wind and solar) or hydro, if you have a water stream nearby.

Until you slash energy usage, though, its not worth the investment in renewable power sources. Conservation is still the cheapest game in town.

One of the most common barriers facing the energy retrofit market is the lack of accountable information and benchmarks to assist energy experts and consultants in creating a clear-cut financial case to demonstrate that investing in energy reduction measures can provide profitable growth.

A few governments/energy research institutes have started taking lead in this field. Deep energy retrofit requires a multi-disciplinary team with a can-do attitude where the disciplines can constructively collaborate with each other.

Design professionals, in particular, should be experienced with integrative design.

In the end I would like to summarise that a successful deep energy retrofit can produce a long-term strategy to phase out energy use in a building to make it super efficient, more desirable to its occupants, and more valuable to owners.

Our endeavour should be to transition from near zero energy buildings to zero energy buildings, and further to energy plus buildings, which will produce surplus energy than what is required in the building.

Reach Ashok by sending an email to ashokjha@universalvoltas.com.

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Studying utility bills covering at least one year, or more, is a good start and it acts as the base line... - MEP MiddleEast