FAQ
Solar radiation has different components, electromagnetic radiation consisting of light, heat or thermal energy, Ultra violet radiation and others. Solar thermal technology deals with the harnessing and utilisation of solar thermal energy for human use. Like process requirement ofheat, water heating, steam generation, cooking or space heating and cooling, and also to generate electricity. It’s unlike photovoltaic (PV) power, which converts a portion of the sun’s electromagnetic radiation directly to electrons and electricity.
Thermal radiation is electromagnetic radiation generated by the thermal motion of particles in matter. All matter with a temperature greater than absolute zero emits thermal radiation.
Solar thermal radiation is natural as it is the radiation for sun that causes it. The maximum intensity of heat energy reaching the top of the atmosphere directly facing the sun is about 1,360 watts per sq. meter, as per the measurements made by the most recent NASA satellite missions, that is not at all harmful to the human beings and is extremely safe.
The Conventional cooling technology could be classified in to Evaporative cooling and Vapour compression cooling. An evaporative cooler, sometimes referred to as a swamp cooler, or desert coolers, utilizes water-soaked pads to cool the air. This process works because a fan pulls hot air into the unit, sending it through a series of pads that helps evaporate the water and the resultant damp air is used to cool the atmosphere. This will be effective in a very dry climate places like, Rajasthan, Delhi, Hyderabad, Middle East countries etc.
The most commonly used Conventional cooling is using Vapour Compression chillers to cool the space. The compressor takes in a low temperature, low pressure refrigerant vapor, and compresses it into a high temperature, high pressure vapor. The heat from the source boils off the refrigerant through phase change heat transfer, and the low temperature, low pressure gas enters the compressor, completing the cycle.
The Hydro Chloro Fluoro Carbon and Hydro Fluoro Carbon refrigerant used in the Conventional cooling technology, are toxic or explosive and thereby dangerous to people's health. There are other problems associated with these Refrigerants.
1. The leakage of Refrigerant gases in to the Atmosphere cause Ozone Depletion and contribute to global warming.
2. The Conventional cooling systems consume higher levels of Electrical energy, that increases the CO2 emissions and contribute to global warming by absorbing infra-red radiations and by holding it in the atmosphere.
The Conventional heating technology consists of either a hot water or a Boiler that uses, fire wood, coal, gases, diesel, Furnace oil or other Fossil fuels or electricity to heat the water. This hot water and steam can be used for coolking, heating of the homes, process heating requirements in the Industry and other purposes.
The conventional heating methods use fuels that are not sustainable in the sense they are not renewable sources of energy. These fossil-based fuels produce smokes that are high in CO2 and CO emissions contribute to global warming by absorbing infra-red radiations and by holding it in the atmosphere.
The diagrams below give the details.
The Conventional heating technology consists basically of a water heater or a boiler and various secondary equipment depending on the application. The conventional heating methods use fuels that are not sustainable in the sense they are not renewable sources of energy. These fossil-based fuels produce smokes that are high in CO2 and CO emissions contribute to global warming by absorbing infra-red radiations and by holding it in the atmosphere.
The conventional heating methods use fuels that are not sustainable in the sense they are not renewable sources of energy. These fossil-based fuels produce smokes that are high in CO2 and CO emissions contribute to global warming by absorbing infra-red radiations and by holding it in the atmosphere.
The Conventional heating technology consists basically of a water heater or a boiler and various secondary equipment depending on the application. The conventional heating methods use fuels that are not sustainable in the sense they are not renewable sources of energy. These fossil-based fuels produce smokes that are high in CO2 and CO emissions contribute to global warming by absorbing infra-red radiations and by holding it in the atmosphere.
The Conventional cooling systems use consume higher levels of Electrical energy, that increases the CO2 emissions and contribute to global warming by absorbing infra-red radiations and by holding it in the atmosphere.
Please find given the charts comparing the conventional and the Natus chiller systems. Carbon foot prints come only from the usage of fossil fuels like coal, gas, diesel, Furnace oil or Electricity generated using Fossil fuels. Natus Solar systems use the thermal energy from the sun to generate hot water and use it as the power source for air conditioning, hot water for the processes and steam. Hence Natus solar systems save Carbon emissions and do not contribute for the CO2 emissions and the resultant Global warming.
It saves around 85% to 90% on the power, and fuels used in cooling and heating.
It saves on CO2 emissions and hence contribute positively for the Global warming.
It does not use Hydro Chloro Fluoro carbon and Hydro Fluoiro Carbon based Refrigerants and hence positively contributes to the reduction of Ozone Layer depletion.
It saves around 85% to 90% on the power, and fuels used in cooling and heating.
It saves on CO2 emissions and hence contribute positively for the Global warming.
It does not use Hydro Chloro Fluoro carbon and Hydro Fluoiro Carbon based Refrigerants and hence positively contributes to the reduction of Ozone Layer depletion.
Yes. Thermal storage systems are provided in the Natus Solar Systems to store sufficient heat or cold energy from the solar heat during the sun shine hours, that can be used during non-sun shine hours thus making the Natus Solar Systems generate energy 7x24x365.
It is similar to using batteries in the PV power generation systems for storage of power.
Yes.
Even in winter season in Cold countries, there is still an amount of solar radiation that supplies heat, though very small. 60% of this solar thermal radiation still gets converted to heat and gets stored as hot water in the Natus Solar Systems.
For example, let us look at Boston, one of the coldest cities in USA with a fair amount of snow and freezing ambient temperatures in winter.
You can see that when in the months of Jan and Feb, when the Ambient temperatures become sub-zero and freezing, there is still a fair amount of solar radiation, falling on the earth surface shown as GHI up to around 3 kw-hr/m2/day and this gets converted in to heat and stored as Hot water by the Natus Solar System.
Natus Solar system will produce enough heat to heat the rooms using this radiation.
We have installed such system in the Embassy of Switzerland building in Delhi and in the thermal power plant in Gujarat, for heating during winter and the same system cools during summer times.
Natus Solar system costs will vary with the location, that is solar radiation dependent, the space available for mounting the panels and the distance from the location for other components that is distance dependant.
Notwithstanding these variations, as a thumb rule, it can be roughly be as follows.
Solar Air conditioning – around USD 6,500/TR
Solar Hot water generation- around USD 4,600/Eq. Tr or
around USD 920/kw-hr.th
Solar Steam generation- around USD 13,500/Eq. TR
around USD 2,700/kw-hr.th
Conventional systems cost vary with the type of chillers in case of solar air conditioning, and depends on the fuel used in the boilers and the efficiencies of the boilers and many other factors.
Notwithstanding these variations, a ball park figure could be given as follows.
Solar Air conditioning – around USD 1,200/TR
Solar Hot water generation- around USD 1,000/Eq. Tr
Solar Steam generation- around USD 4,500/Eq. TR
As there is around 85 to 90% of energy saving compared to the conventional systems, the pay back of the incremental initial cost of Natus Solar System, compared to the Conventional Systems is around four to seven years depending upon the nature of the system and hence the ownership costs become zero after that and there is a saving coming through every year, over the life cycle of around 20 to 25 years, in case of Natus solar systems.
In case of Solar air conditioning, Energy meters are used to measure both the TR generated and the electrical power saved.
In case of the Solar hot water and the steam generation systems, Energy meters and flow meters are used to find the thermal energy generated and the total energy saved.
In all cases, pyranometers and temperature sensors and flow meters are used to measure the solar conversion value and the efficiency.
In case of Solar air conditioning, Energy meters are used to measure both the TR generated and the electrical power saved.
In case of the Solar hot water and the steam generation systems, Energy meters and flow meters are used to find the thermal energy generated and the total energy saved.
In all cases, pyranometers and temperature sensors and flow meters are used to measure the solar conversion value and the efficiency
The market has to be educated on the Natus solar system, its advantages and the benefits, and the market has to be shown the actual examples of installations. They also have to be educated as to how retro fittings can be made with their existing systems so that with minimal changes, they can derive the benefits of the Natus Solar Systems.
But for the pumps, that also have redundancy built in, there is hardly any rotating parts and hence hardly any maintenance is involved. The other maintenance involved will be hose cleaning of the collectors that too only a few times a year, depending on the dust levels involved. The maintenance costs would be less than 0.5% of the project cost/ annum, that is negligible.