Water is precious. Save it
Catching running rainwater from various sources can help us capitalize on a vast water resource and solve water woes
What is rainwater harvesting?
Rainwater harvesting is a system by which rain is caught from all kinds of surfaces such as rooftops, gardens, roads, pavements, etc, and is purified and re-used for daily purposes. It can be used to perform two basic functions:
a) Recharging groundwater sources for later use;
b) Storing rainwater for immediate use and consumption.
Why do we need it?
With groundwater levels reaching dangerous lows it has become imperative for citizens to look for alternative sources of water, or the situation will grow from bad to worse very soon. This system has been operational in the developed countries for over a decade and has successfully managed water conservation. By catching running rainwater from various sources we can capitalise on a vast water resource and generate hundreds and thousands of litres of water every season that can help solve water woes. For example, a water tanker that brings water to your homes from unknown sources and unclear sanitation standards cost about Rs 1,000 to Rs 2,500 for about 10,000 litres of water. The RWH system gives you the same quality of water that you put into it without any extra cost.
What are the conditions that impact the structure of the apparatus?
The harvesting system depends on the following factors:
Amount of annual rainfall in the given area.
At an average, all areas where the groundwater level is more than 8 metres below the surface, groundwater recharging mechanism is advised to ensure that the water table is maintained for later use. Whereas those areas where the table averages between two and eight metres can go in for the storing device for cleaning and storing the water for use.
Demand for water generated.
The demand for water along with the available catchment area determines the size of the storage facility that is used. In building complexes and residential colonies, residents in the same building pool money and benefit from the water that is saved on their common rooftops, thus forming an economical and easy maintenance harvesting system. The materials and cost incurred during the whole installation and maintenance procedure. If the residence is in a condominium complex or a bungalow 75 to 80 percent of the RWH system is already in place and only the plumbing needs to be reoriented and the whole RWH mechanism is attached to the storm drain network that has already been established.
This mechanism will bring rainwater down using closed PVC pipes directed towards a sump (pit) and a simple three-part filtration unit consisting of sand, brick jelly and broken bricks.
Where sumps are unavailable old wells can be cleaned and used or new baby wells (2ft/l6ft diameter) can be constructed based on soil structure. For storing water for immediate use, the pipes bring down the water passing through a very small filtration valve containing wire mesh, small pebbles, etc, leading into large storage Sintex tanks placed at convenient locations for frequent usage. The water is then treated with chlorine tablets or boiled for drinking purposes.
Depending on the kind of model in your household and the terrain, the average cost of setting up an RWH system varies between Rs 2,000 to Rs 20,000. How does one ensure maintenance and quality standards? Since groundwater is replenished, care must be taken that leaking sewage pipes do not contaminate the recharge pit, etc, the filtration plant if cleaned frequently removes foreign matter, giving you safe usable water from your rooftop. The system should be cleaned twice a year preferably before and after the monsoon and does not cost much.
The Delhi government has assured to provide experienced staff for the annual cleaning and maintenance of storm water drains, etc, for all complexes that have taken the RWH initiative.
THERE ARE about 73 rain water harvesting (RWH) projects that have been set up in and around Delhi, for about four to five years now yielding tremendous results. A number of case studies prove its success.
"The Panchsheel Park Residents Association in New Delhi invested about Rs 8 lakh for the installation of an RWH system over 95 acres, and the average cost per household was only Rs 500. And today, the water table of the area has maintained itself for the 4th consecutive year where all other parts of south Delhi face severe water deficiency" — Salahuddin, Centre for Science and Environment
"We always believed a school to be an institution that sets examples and influences society in the most positive ways. This is why when the whole of Delhi was facing massive water shortages around 1999, our school set up the RHW plant with the help of CSE and the Central Government Water Authority, and we were in fact one of the first institutions in New Delhi to do so. The amount of awareness and sensitivity it has generated amongst the students has been overwhelming and now the whole project is completely monitored by students" — Madhu Bhatnagar, Deputy Head of Sri Ram School, New Delhi
"The year 2002 had been stressful, with Delhiites reeling under a major water crisis. But we have been spared now. We are using water frugally, but there is enough for us to feel comfortable" — Kulbhushan Oberoi, Chairperson, Oberoi Education Society commented, for Mira Model Public School
"No one knew what rainwater harvesting was all about when we decided to take it up in our college. As the work began the students grew curious and wanted to know more about it. Now everyone wants to adopt it" — Aruna Ludra, lecturer, Janki Devi College for Women
"We have actually recorded a three-metre rise in the water table within one-and-a-half-years! This is very exciting" — Prof PS Srivastava, Dean, Faculty of Science, Jamia Hamdard University
With New Delhi receiving an average of about 611mm of rain annually, and a rain water harvesting potential of about 450 billion litres, this figure can take care of about 35 percent of Delhi's demand of 838 million gallon litres per day. Many such cases are available to illustrate the system's advantages.
This article by DIVASHRI SINHA appeared in Tehelka
Save Energy. Tips you can use
Save Energy and Water. It is too precious to waste.
Here are some tips how to save it
One of the best energy-saving devices is the light switch. Turn off lights when not required.
Many automatic devices can help in saving energy used in lighting. Consider employing infrared sensors, motion sensors, automatic timers, dimmers and solar cells wherever applicable, to switch on/off lighting circuits.
As far as possible use task lighting, which focuses light where it's needed. A reading lamp, for example, lights only reading material rather than the whole room.
Dirty tube lights and bulbs reflect less light and can absorb 50 percent of the light; clean your tube lights and lamps regularly.
Fluorescent tube lights and CFLs convert electricity to visible light up to 5 times more efficiently than ordinary bulbs and thus save about 70% of electricity for the same lighting levels. An electronic choke can save up to 30% energy as compared to electro magnetic chokes.
Ninety percent of the energy consumed by an ordinary bulb (incandescent lamp) is given off as heat rather than visible light.
Replace your electricity guzzling ordinary bulbs (incandescent lamps) with more efficient types. Compact fluorescent lamps (CFLs) use up to 75 percent less electricity than incandescent lamps. o A 15-watt CFL bulb produces the same amount of light as a 60-watt incandescent bulb.
Room Air Conditioners
Use ceiling or table fan as first line of defense against summer heat. Ceiling fans, for instance, cost about 30 paise an hour to operate - much less than air conditioners (Rs.10 per hour).
You can reduce air-conditioning energy use by as much as 40 percent by shading your home's windows and walls. Plant trees and shrubs to keep the day's hottest sun off your house.
One will use 3 to 5 percent less energy for each degree air conditioner is set above 22°C (71.5°F), so set the thermostat of room air conditioner at 25°C (77°F) to provide the most comfort at the least cost.
Using ceiling or room fans allows you to set the thermostat higher because the air movement will cool the room.
A good air conditioner will cool and dehumidify a room in about 30 minutes, so use a timer and leave the unit off for some time.
Keep doors to air-conditioned rooms closed as often as possible.
Clean the air-conditioner filter every month. A dirty air filter reduces airflow and may damage the unit. Clean filters enable the unit to cool down quickly and use less energy.
If room air conditioner is older and needs repair, it's likely to be very inefficient. It may work out cheaper on life cycle costing to buy a new energy-efficient air conditioner.
Make sure that refrigerator is kept away from all sources of heat, including direct sunlight, radiators and appliances such as the oven, and cooking range.
When it's dark, place a lit flashlight inside the refrigerator and close the door. If light around the door is seen, the seals need to be replaced.
Refrigerator motors and compressors generate heat, so allow enough space for continuous airflow around refrigerator. If the heat can't escape, the refrigerator's cooling system will work harder and use more energy.
A full refrigerator is a fine thing, but be sure to allow adequate air circulation inside.
Why we should use CFL?
The National Electricity Policy recently notified by the government of India mentions, "Energy efficient lighting technologies should also be adopted in industries, commercial and domestic establishments." The widespread use of incandescent (also called GLS) lamps by households and commercial users are a major area of potential efficiency gain in lighting. For example, to get the same light output, one 60W GLS bulb can be replaced by a 15W Compact Fluorescent Lamps (CFLs). This reduces the power demand by nearly 45W or by three fourth of the original. Replacement of just one such GLS lamp that is operational at the peak time by every household in the country can reduce the peak power demand by over 5,000 MW! The potential saving is much larger when we consider that 5 5 % of rural households are yet to be electrified. Under the rural electrification initiative, the government is planning to electrify the remaining households' in the coming five years. This increases the potential saving, through use of CFLs, to nearly f 0,000 MW! Hence, rapid and extensive penetration of CFLs can help us substantially mitigate the peak power shortage in the country.
Economics of CFLs for bulk consumers
The retail price of CFL has a wide range, but most lamps are priced between Rs.70 and Rs. 150, depending on rating and manufacturer among other things. Despite this higher cost of CFL, compared to the GLS lamps; their economics is very attractive. Lower consumption of electricity and longer life of CFL make them more economical. A reasonable quality CFL, can pay back the higher initial cost of CFL, in short period of 15% to 25% of its life; depending on the electricity tariff. For the remaining 75% to 85% of CFL's life, it results
in net saving for the consumer. In other words, when the electricity tariff is Rs.3/kWh, a CFL operating for just two hours a day, saves electricity to pay back the higher initial cost in a period of eight months. For lamps operating for longer duration the payback is proportionately faster.
Economics for load management
Since the lighting load forms a part of peak load for the utility and that too mostly by domestic users which generally receive subsidized tariffs as compared to other categories, it makes sense to reduce the peak load by use of CFL especially in domestic sector. The economics work out to be very attractive as the reduction in demand provides utility with additional capacity to supply high paying customers. In some developed countries even free distribution of CFLs by the utilities has worked very economic. The utilities in India must exploit this opportunity offered by CFLs.
Purchase of CFLs on life cycle cost rather than first cost basis by the government |H agencies. Monitoring the performance of CFLs and sharing of experiences with other departments on regular basis.
Considering the very large number of such houses in the country, we have to address this problem. Reduction of cost of CFLs is one method to address this problem. Bulk purchase of one or two standardised lamps, rationalisation of taxes on the CFLs and cost reduction measures by the manufacturers can help substantially help. There is a sizable scope for such
cost reduction without affecting rather improving the quality of CFL. If the utility has a CFL leasing program, the first cost barrier faced by consumers can be overcome. A 15-Watt CFL, which is equivalent to a 60 W bulb, would last about 6,000 hours (40 months) and may cost Rs. 120. The utility can recover this cost through monthly bills at the rate of Rs.10 per month for 12 months. This is nearly a "no-cost" affair for the utility except for some modifications in the billing and accounting procedure.
Poor consumers with low usage are offered low electricity tariff as the lifeline tariff. In many states, the tariff paid by these consumes about Rs. 1.5 / kWh. In such a case, even the cost of CFL leasing is more than the electricity saving in the initial year. Hence, it does not make economic sense for these consumers to take CFLs even through the leasing program. But in that case, their consumption remains high and the utility continues giving subsidy on their electricity use. In addition, the utility can share part of its potential saving (due to reduced subsidy to these consumers), with such consumers to reduce the monthly installment of CFL. The utility saving is much more than what appears to the eye, in terms of difference between average cost of supply and the tariff by the poor households. The lighting usage is peak time usage, so the saving has to be calculated considering the reduction in peak T&D losses, reduced need for peak power purchase and so on. The required contribution by utility for this is small compared to the scale of its operation.
Several consumers are unwilling to buy a CFL to replace much cheaper GLS, and end up paying much more for the electricity usage of the lamp. The consumers not using CFLs are faced with some barriers, which can largely be divided in three categories.
Some of the barriers you should overcome while buying a CFL
Information barrier: A large section of consumers are still unaware of the large benefits of using CFLs. The consumer awareness should be increased through advertisement and other measures to encourage more consumers use CFLs.
'it Inappropriate fitting: The consumers having lampshades or luminaries unsuitable for CFLs do not change the luminaries for using CFLs. But as smaller CFLs and decorative luminaries especially designed for CFLs are becoming more common, this barrier would diminish. o First cost barrier: i) Most of the government tenders are based on lowest price and unless the benefit of CFL on life cycle cost is recognised and approved it becomes difficult for the government agencies to adopt this new technology.
The problem is acute for the very poor consumers. Nearly half of the residential consumers in most states have electricity usage of less than 50 kWh/month. The monthly electricity bill of these consumers is barely Rs.50 to Rs.85. These consumers are too poor to afford CFL at present prices. These would be over 50 million households. Additionally about 100 million un-electrified houses, which would be connected to the grid in the coming five years, would also fall in this category.
Courtesy : The Economic Times
Ahmedabad is the Industrial and Commercial capital of Gujarat. The political capital remains at Gandhinagar, 30 kilomters apart. The city, on the bank of river Sabarmati, lies 230 1' North Latitude and 720 41' East Longitude and is the seventh Largest City of India.
The city is well connected by rail, roads and airways with all the important cities of the country. It's area is 190.84 Kms and expanding.