Passive Heating Issues - Essay Example

Passive Heating Heating in homes is usually accomplished mechanically by a suitable system that utilises energy to do the heating. That energy usually comes primarily in the form of gas or electricity as that case maybe. In either situation the input energy for the system is secured from non-renewable sources of energy (fossil fuels). The use of solar energy for the heating in houses or cooling in cases of hot summers is palpable mainly through the passive design of the building itself. In this section a critical analysis on the passive heating strategy in the buildings is presented to the reader. The analysis comprises of examples from both the KYOTOi protocol of the United Nations and the Energy performance of Buildings Directive of the European Union that is being enforced across the west for energy efficiency and savings of the conventional sources of energy. The analysis predominantly focuses upon the energy efficiency of the buildings using the passive heating strategy. Nuclear sources also cater the energy requirements in certain cases where it generates the electricity required for the generation of electricity. In all the aforementioned cases, the pollution into the atmosphere due to heating is enormous indirectly because the generation of electricity in case of electric heaters causes pollution of the atmosphere if not in the immediate vicinity of the users whilst the gas heating systems cause the pollution in the vicinity itself. The atmosphere being a single entity, the greenhouse effect spreads across the entire spread of the atmosphere irrespective of the location of emission of Carbon Monoxide and Carbon di-oxide gases. David Taylor (2005)ii further argues that the main reason for the increase in the energy consumption by the domestic buildings is the inability or the reluctance of the people to utilise the energy of sunlight and natural means for cooling during the summer. This is also due to the fact that the increase in the density of the buildings in the urban areas like the busy areas of London where the density of the domestic buildings has increased by more than 10 times in the six years as argued by W. L. Lee and F. W. H. Yik (2005)iii. The study by the authors have proved that the population density increase in the urban areas has accompanied with the steep density of the buildings thus presenting a congested environment for the energy management and the use of natural resources of energy for cooling during the summer. Furthermore, the use of each kWh (kilo Watt hour) of energy Douglas Lancashire (2005) has identified the emission rations as described below 1.5 lb (680 grams) of Carbon Di-Oxide 0.2 ounce (5.67 grams) ounces of Sulphur Di-oxide and 0.08 ounces (2.27 grams) of nitrogen oxides The information presented above reveals that through saving every kWh of electricity alone, a building could contribute to the reduction of emission and pollution of the atmosphere. Even though the pollution is not caused at the surroundings of the building, the fact that the consumption of energy is directly proportional to the emission of gases and pollution by the power generation plant justifies the need for energy efficiency in the buildings. The aforementioned makes it clear that the costs involved with the energy consumption and the maintenance of the heating systems is a critical element both to the homeowners, which is a direct cost whilst the indirect cost is mainly the loss of non-renewable sources of energy and atmospheric pollution. In order to overcome this problem, passive heating is proposed by researchers as an effective alternative. Passive heating as argued by Raymond Ward (2005) is the method of using the non-conventional sources of energy like the solar energy to generate the energy required to cater the heating requirements in domestic buildings. Another source of energy is the wind energy that is in abundance especially in the UK where the sunlight is treated as a rare commodity with only short spells of summer every year. Alongside, passive heating can also be accomplished through clever house design and construction to ensure that this potential for heating using the solar energy or to retain the heat energy for a longer period of time within the rooms thus reducing the consumption of non-renewable sources of energy whilst improving the efficiency of the heating systems. Below a discussion on a few elements that accomplish passive heating effectively is presented to the reader. Insulation: Effective insulation is one of the most cost-effective methods of reducing energy consumption for space heating in homes. Surveysiv show that a poorly insulated 1970s home in the UK will utilize 13,000 kWh per year to accomplish heating. From the calculation shown before the total quantity of harmful gases emitted by that home causing atmospheric pollution is: 8840 kg of Carbon Di-Oxide 73.71 kg of Sulphur Di-oxide and 29.51 kg of nitrogen oxides The aforementioned makes it clear that this conventional method of heating should be addressed immediately in order to reduce the pollution. A modern home on the other hand, with reasonable standards of insulation will only utilise 4,000 kWh to do the same work (Green Energy). The results of a similar calculation as mentioned above reveals the emission levels as 2720 of Carbon Di-Oxide 22.68 kg ounces of Sulphur Di-oxide and 9.08 kg of nitrogen oxides 'Super-insulated' homes in Sweden can survive without mechanised heating systems and are kept comfortably warm by the waste heat generated by cooking, lighting and also the body heat of occupants. A brief insight on the design standards to achieve passive heating is presented to the reader below. ASHRAE recommends between R-30 and R-52 for attic space, R-13 and R-21 for cathedral and flat roofs, R-13 and R-21 for walls and R-13 and R-30 for floors. For colder climates, as this essay proposes to utilise, the higher values are recommended. For windows in cold climates it also recommends double-glazing (half inch air space) with non-metal or insulating frames coupled with a winter low-e (e less than .05) coating on the glass to retain more internal heat. (Energy Tip for the Heating Season, ASHRAEv) Retaining Passive Solar Gain: One of the principal strategies for heating homes efficiently and cheaply with least utilisation of mechanised systems is by designing and constructing the house in such a manner that the house gets maximum exposure to the sun's rays and the energy that is inducted into the house as a result is retained to the maximum. The solar energy that is let into the house is called the 'solar gain'. Surveys have proved that as much as 14% of heating demand in UK homes is provided by solar gain. (Green Energy) Inducting the following design features into the building of the house can increase this percentage. The house should be built in such an oriented manner that most frequently used rooms have windows opening southward. The windows on the south should be larger than those on the north so that the house gets maximum exposure to the sun from the south while cold winds from the north are kept out, reducing possibilities of chilling. Building materials that store heat and increase the 'thermal mass' of the house should be used. Houses in clusters should be laid out in such a manner that they do not overshadow each other. (Green Energy) Ultra-modern building technology-inducting bionics utilise materials and surfaces in such a manner that the maximum amount of the sun's energy that falls upon the house is inducted into it and retains but exploration into this technology is beyond the scope of this report. Nevertheless maximum use of modern materials and techniques that do apply to such conventional buildings shall be made. The above arguments justify that the smart use of materials in the building design will increase the level of passive heating thus reducing the use of conventional sources of energy as well as limiting the use of solar energy. Weather-stripping: The ASHRAE recommends that caulking, installing weather-stripping or using spray-in foams around windows and doors, exterior walls, between heated and unheated spaces, garages, basements, crawl-spaces and attics can keep the air in the rooms warm making it clear that the air circulation within the house fitted with weather stripping equipments will reduce the consumption of energy. It also recommends that draperies and shades should be opened on south-facing walls in the daytime when the sun's rays can enter the house and provide natural warmth to the residents. Keeping it closed during night times will prevent the entry of cold air. This is a very simple technique but very effective (Energy Tips for the Heating Season, ASHREA). Although, these passive-heating strategies may not be successful in raising the temperature of a house situated in a cold climate to comfortable levels in isolation of some form of mechanised heating. In the next section an analysis on the reduction strategies on conventional heating systems is presented to the reader where the design considerations to implement passive heating methods in conjunction with the conventional methods is presented to the reader. Conclusion: From the above discussion it is clear that the solar energy and energy savings can be accomplished not only through the process of effective material usage or through passive heating but mainly through the effective deployment of the aforementioned in combination to achieve effective energy savings. Read More