The new device, developed at MIT University, floats on top of the water and manages to convert 20% of the absorbed solar energy into steam at XNUMX degrees Celsius without using expensive optical devices to focus sun rays.
![A sponge-like device that includes a sheet of plastic bubbles inside that absorbs solar radiation and heats the water underneath to create steam through its pores [courtesy George Ni of MIT]](https://www.hayadan.org.il/images/content3/2016/09/a92031ffd08329b0060062decad956d1_L1-500x281.jpg)
Recently, an innovative and cheap system was developed to convert solar energy into thermal energy, such that it can produce steam with the help of the sun's rays. The solar system could help technologies based on steam, such as water desalination, sewage treatment, home heating, sterilization of medical equipment and electricity generation, become much more efficient and available.
The new device, developed at MIT University, floats on top of the water and manages to convert 20% of the absorbed solar energy into steam at XNUMX degrees Celsius without using expensive optical devices to focus the sun's rays, and in addition, it consists of cheap commercial materials, including plastic bubble wrap and polystyrene foam. "The project is an excellent demonstration
It allowed us to produce steam with the help of solar energy without relying on direct solar radiation," explains the researcher. "The technology is particularly suitable for countries with a dusty environment since it utilizes the full spectrum of the sun's rays for thermal applications and not just the direct radiation," explains the researcher. The research findings have long been published in the scientific journal Nature Energy.
The design of the system is quite simple: a sponge-like floating device consisting of an absorbent material with spectral selectivity, which allows the energy of visible light coming from the sun's rays to be absorbed by the device while reducing the amount of heat returned to the atmosphere. The result of capturing the heat significantly improves the efficiency ratio of the device in terms of converting sunlight into steam. The absorbent material is between an upper layer of plastic bubble sheet that allows the sun's rays to be absorbed, while reducing the amount of heat lost to the air through heat conduction, and a lower insulation layer consisting of foam, which allows the entire device to float on a body of water while reducing the thermal loss of the heat generated to the water below . The flotation device that collects functions as a sponge that constantly sucks up water and evaporates it, creating a continuous stream of steam. The solar device demonstrated its performance at MIT, where the researchers showed its ability to quickly reach a temperature of XNUMX degrees Celsius and produce steam during periods of little direct sunlight, for example during the winter months and periods of high cloud cover. "The technology we developed is particularly effective in areas with a desert climate, such as Abu Dhabi, within possible applications such as wastewater treatment, seawater desalination, and even electricity generation," said the chief researcher.
The news about the study
A sponge-like device that includes a sheet of plastic bubbles inside that absorbs solar radiation and heats the water underneath to create steam through its pores [courtesy George Ni of MIT]
8 תגובות
Miracles
Today's solar water heater in the summer in Israel really has enough water for even a large family. But if you also use other devices, I don't think it will be enough. Apart from that, in the future they will need the real estate on the roof to produce electricity and even better it will be possible to heat water without taking up space. Besides, I'm pretty sure it can save electricity for the air conditioner itself because the cooler will be more efficient.
And most importantly, this is the end of the Israeli experience of walking down the street on a hot day and suddenly catching an even hotter gust.
(of course there are also disadvantages of a higher installation price)
American washing machines still have access to a hot water tap in addition to cold
20 years ago my grandmother had an Indesit (Matalia) washing machine and it had a connection to external hot water.
Unfortunately today it is not possible to find (in Israel) a washing machine with an external hot water inlet.
Probably not economic for the producer/importer.
A.
This is a very interesting idea. We build small computers with water cooling and there is a very significant difference in noise.
The issue may be that in the summer, when the air conditioner is used a lot, there is enough hot water from the solar water heater and therefore the economic advantage is low. But in the case of hotels for example, it can be an effective idea.
In any case, in my opinion only the saving in noise is worth the investment!
Markets
I would be happy if you elaborate further.
In any case, you will agree with me about laundry and dishwashing.
In the summer, it is theoretically possible to cool the motors of the air conditioners with water (that is, pipes that will flow without direct contact of the water inside the motor) instead of cooling with air, which is noisy and heats the air around the house. In my opinion, this will also allow the air conditioners to be more efficient and can also be used to heat the water.
It is not recommended to drink water that has passed through the household pipes when it is hot.
It's interesting how much more efficient it is than a solar heater like the one that is usually installed in Israel (even though the boilers in Israel usually reach a much lower temperature). I have been thinking for a long time that it is a shame that the use of the sun in Israel is only used for heating for bathing and not for dishwashers and washing machines. It is also possible with proper education of the public to get used to boiling water for drinking and cooking from the hot water. Even if this water is only 30 degrees, you can save between 15-20 percent of the electricity/gas in the process.
I can easily see how the coal can be replaced with this, at least during the hot summer days