EMBODIED AND OPERATING ENERGY + EVALUATION TOOLS FOR BUILDING ENERGY C.S.Yadhu Krishnan

Embodied energy The energy required to extract, process, manufacture, transport and install building materials.

Embodied energy types Initial embodied energy –Direct energy: Transportation and construction processes –Indirect energy: Acquire, process and manufacture Recurring embodied energy Energy of building maintenance and renovation (exclusive of janitorial)

–Lumber 5,229 Btu/bd ft –Brick 13,570 Btu each –Aluminum 90,852 Btu/pound Embodied energy: materials

–Concrete 95,738 Btu/cu yd* –Glass 41,828 Btu/sq ft –Steel 21,711 Btu/pound

Embodied energy: building type Residential 700,000 Btu sq ft 6 gal/ sq ft Sea Ranch, California

Embodied energy: building type Retail: 940,000 Btu sq ft 8 gal/sq ft Urbana IL: Lincoln Square Mall

Embodied energy B uilding type Education 1,400,000 Btu sq ft 12 gal/ sq ft Yale School of Architecture, New Haven CT

Embodied energy: building type Office 1,640,000 Btu sq ft 14 gal/sq ft Chicago IL, City Building

Embodied Energy : Embodied Energy is the sum of all the energy required to produce goods or services, considered as if that energy was incorporated or 'embodied' in the product itself. The concept can be useful in determining the effectiveness of energy-producing or energy- saving devices (i.e. does the device produce or save more energy that it took to make it?), of buildings, and, because energy-inputs usually entail greenhouse gas emissions, in deciding whether a product contributes to or mitigates global warming. Embodied energy is an accounting method which aims to find the sum total of the energy necessary for an entire product life-cycle. Determining what constitutes this life-cycle includes assessing the relevance and extent of energy into raw material extraction, transport, manufacture, assembly, installation, dis- assembly, deconstruction and/or decomposition as well as human and secondary resources. Different methodologies produce different understandings of the scale and scope of application and the type of energy embodied.

Methodologies of embodied energy: Embodied energy analysis is interested in what energy goes to supporting a consumer, and so all energy depreciation is assigned to the final demand of consumer. Different methodologies use different scales of data to calculate energy embodied in products and services of nature and human civilization. International consensus on the appropriateness of data scales and methodologies is pending. This difficulty can give a wide range in embodied energy values for any given material. In the absence of a comprehensive global embodied energy public dynamic database, embodied energy calculations may omit important data on, for example, the rural road/highway construction and maintenance needed to move a product, human marketing, advertising, catering services, non-human services and the like. Such omissions can be a source of significant methodological error in embodied energy estimations. Without an estimation and declaration of the embodied energy error, it is difficult to calibrate the sustainability index, and so the value of any given material, process or service to environmental and human economic processes.

Operating energy “Energy consumed during the in-use phase of a building's life is called as operating energy” Reducing the operational energy use and increasing durability should be the prime concerns of architects who wish to design and build “green” buildings.

Operating energy Average energy consumption Btu/sq. ft Commercial Buildings (non malls) Before , – , – , – , – , – , – , – ,703

Logan County Illinois Courthouse 81,000 Btu/sq. ft. No wall insulation No central A/C Operating energy historic building

Operating energy LEED platinum building The Lewis and Clark State Office Building Jefferson City, Missouri 68,000 Btu/yr/sq ft Leadership in Energy and Environmental Design

Residential operating energy btu/sq ft/yr Northeast MidwestSouth West 47,700 46,90037,000 43,400 National Average = 43,700 Btu/sq ft/yr*

Heating and cooling systems play a significant role in the increase in the energy efficiency of buildings by using innovative technologies and renewable energy systems. The European Commission underlines the contribution of the heating and cooling systems in the recast EPBD (Energy performance of buildings directive) and prepares a new mandate to update the CEN (European committee for standardization) standards linked to EPBD. To design energy efficient buildings and systems, professionals need sophisticated tools. Tools able to show the positive impact on the energy efficiency of heating and cooling systems and based on verified performance data. No "details" can be neglected in low energy or nearly net zero energy houses or buildings Evaluation Tools For Building Energy

Breakdown of energy applications in buildings

The overall energy consumption of a single family house in a building stock is about 200 kWh per m 2 and year (delivered energy). The losses of the technical building systems are representing about half of the consumption. This shows that reducing the energy losses due to poor design and operation of technical building systems contribute a very important effect on the improvement of the overall energy efficiency of buildings. For existing building this means modernization of installation with innovative technology. This positive contribution must be made "visible" for the regulator responsible for the national building regulation and also for the consumer by a uniform, transparent evaluation of building technical systems based on standardised product and system characteristic.

The energy efficiency of heating and cooling systems is determined by calculating the thermal systems losses and the auxiliary consumption.

From the methods to the tools – heating and cooling systems needs high quality and easy to use software tools Technical building systems have the reputation to be complicated in data acquisition and in the evaluation of the performance. The assumption that the influence of technical building systems on the total energy use is secondary compared with other improvements, especially in low energy houses is false. The new standards evaluating in a more detailed way the contribution of heating and cooling systems to the overall energy use will show this!.. Based on these standards, software tools have to be developed for easy computation and data acquisition of technical building systems.

Tool requirements The aid decision-making tool should give the stock manager some information to evaluate the energetic performance and suggest some improvement to increase their efficiency. These information could be: The primary energy consumptions, The corresponding CO2 emissions, The energy performance classification (from A to G): it is an indicator of energy performance and CO2 emission (by analogy with the classification of the products electric household appliances). It allows users of this tool to easily show the energy performance. The improvement suggestions, their costs, the time of depreciation, the envisaged energy savings and their impact on the energy performance classification.