Wednesday, December 3, 2008

Evacuated Collector Tubes

In a solar water heater system, special coatings on the evacuated collector tubes are activated when exposed to sunlight, causing the collector temperature to reach upwards of 300 degrees. A water-glycol solution is circulated through the collectors, which transfers the heat into a built-in heat exchanger in the water tank, heating the water. A typical solar water heating system can provide hot water for a family of 4-6 people with larger and smaller systems available. Solar water heaters are also used in a wide range of commercial applications such as laundries, hospitals, dormitories, and various manufacturing processes.  

Thursday, November 13, 2008

How much energy can a solar thermal collector produce?

Using this energy calculator you may determine how much energy  solar collector will produce each day/month/year. The way you utilize this energy is up to you. You can heat water for showering and washing clothes, or central heat a building. In fact one integrated system can complete both these functions.

You can also use these values to help you calculate how much energy you can save by using  solar collector.

In order to calculate energy output you must input the following variables:
Insolation Level - Before you calculate your energy output, you must know your solar insolation level. Take note of your max and min levels throughout the year as well as the annual average value. When assessing potential energy savings, input annual average insolation, and take note of the "per year" energy output value. 
Energy must be input in the unit kWh/m
2/day. 1 kWh/m2/day = 317.1 Btu/ft2/day

Collector Size - You must enter the collector size in absorber surface area.
The absorber surface area of the various tubes sizes are as follows:
- 58/1800 = 0.08m
2 per tube. Therefore  20 tube = 1.6m2 absorber area
- 58/1500 = 0.067m
2 per tube 

Energy Cost - Enter cost per kWh in your local currency 
(may need to convert from m
3 or Therms)
1 therm = 29.3kWh = 100,000Btu = 105.5MJ
Natural Gas is 39MJ/m
3 = 10.83 kWh/m3
LPG Propane (liquid) = 25.3MJ/L = 7kWh/L
LPG Propane (gas) = 93.3MJ/m
3 = 25.9kWh/m3 

Please note:
- Collector peak efficiency is only achieved when ambient temperature and water temperatures are the same. During normal use, this is only likely to happen for a short period of time each day, and usually only when ambient temperatures are high (summer). Therefore during normal use, the solar collector can not always perform at such a high level of efficiency. This is true for all evacuated tube and flat plate collectors. In order to provide more realistic figures, the above calculations are based on "normal" operating conditions under which the difference between ambient temp and manifold water temp is around 30-40
oC.


- Monthly and annual values are calculated using 28 days and 336 days respectively to account for days of very low solar radiation.

- Energy output values are approximations. Actual energy output and overall system efficiency will depend upon installation location, climate, insulation, system configuration and many other factors. On rainy or heavily overcast days energy output will be greatly reduced.

- Energy is produced in the form of heat. In transporting and converting this energy, such as for air conditioning or central heating, some energy (heat) will be lost, as no system or insulation is 100% efficient.More information, please write me mail: Jetwen520@hotmail.com 


What is Heat Pipe?



Heat pipes might seem like a new concept, but you are probably using them everyday and don't even know it. Laptop computers often using small heat pipes to conduct heat away from the CPU, and air-conditioning system commonly use heat pipes for heat conduction.
Structure and Principle

The heat pipe is hollow with the space inside evacuated, much the same as the solar tube. In this case insulation is not the goal, but rather to alter the state of the liquid inside. Inside the heat pipe is a small quantity of purified water and some special additives. At sea level water boils at 100oC (212oF), but if you climb to the top of a mountain the boiling temperature will be less that 100oC (212oF). This is due to the difference in air pressure.

Based on this principle of water boiling at a lower temperature with decreased air pressure, by evacuating the heat pipe, we can achieve the same result. The heat pipes used in AP solar collectors have a boiling point of only 30
oC (86oF). So when the heat pipe is heated above 30oC (86oF) the water vaporizes. This va pour rapidly rises to the top of the heat pipe transferring heat. As the heat is lost at the condenser (top), the va pour condenses to form a liquid (water) and returns to the bottom of the heat pipe to once again repeat the process.

At room temperature the water forms a small ball, much like mercury does when poured out on a flat surface at room temperature. When the heat pipe is shaken, the ball of water can be heard rattling inside. Although it is just water, it sounds like a piece of metal rattling inside.

This explanation makes heat pipes sound very simple. A hollow copper pipe with a little bit of water inside, and the air sucked out! Correct, but in order to achieve this result more than 20 manufacturing procedures are required and with strict quality control.

Quality Control

Material quality and cleaning is extremely important to the creation of a good quality heat pipe. If there are any impurities inside the heat pipe it will effect the performance. The purity of the copper itself must also be very high, containing only trace amounts of oxygen and other elements. If the copper contains too much oxygen or other elements, they will leach out into the vacuum forming a pocket of air in the top of the heat pipe. This has the effect of moving the heat pipe's hottest point (of the heat condenser end) downward away from the condenser. This is obviously detrimental to performance, hence the need to use only very high purity copper.

Often heat pipes use a wick or capillary system to aid the flow of the liquid. Heat pipes can be designed to transfer heat horizontally, but the cost is much higher.

The heat pipe used  two copper components, the shaft and the condenser. Prior to evacuation, the condenser is brazed to the shaft. Note that the condenser has a much larger diameter than the shaft, this is to provide a large surface area over which heat transfer to the header can occur. The copper used is oxygen free copper, thus ensuring excellent life span and performance.

Each heat pipe is tested for heat transfer performance and exposed to 250
oC (482oF) temperatures prior to being approved for use. For this reason the copper heat pipes are relatively soft. Heat pipes that are very stiff have not been exposed to such stringent quality testing, and may form an air pocket in the top over time, thus greatly reducing heat transfer performance.

Freeze Protection

Even though the heat pipe is a vacuum and the boiling point has been reduced to only 25-30oC (86oF), the freezing point is still the same as water at sea level, 0oC (32oF). Because the heat pipe is located within the evacuated glass tube, brief overnight temperatures as low as -20oC (14oF) will not cause the heat pipe to freeze. Plain water heat pipes will be damaged by repeated freezing. The water used in Apricus heat pipes still freezes in cold conditions, but it freezes in a controlled way that does not cause swelling of the copper pipe.


More information, please write me mail: Jetwen520@hotmail.com 

Wednesday, November 12, 2008

Solar Evacuated Tube For Solar Water Heater


Evacuated tubes are the absorber of the solar water heater. They absorb solar energy converting it into heat for use in water heating. Each evacuated tube consists of two glass tubes made from extremely strong borosilicate glass. The outer tube is transparent allowing light rays to pass through with minimal reflection. The inner tube is coated with a special selective coating (Al-N/Al) which features excellent solar radiation absorption and minimal reflection properties. The top of the two tubes are fused together and the air contained in the space between the two layers of glass is pumped out while exposing the tube to high temperatures. This “evacuation” of the gasses forms a vacuum, which is an important factor in the performance of the evacuated tubes.

More info, Please write me mail: Jetwen50@hotmail.com 

Tuesday, November 4, 2008

Super Energy Heat Tube Applications!!!


This is New Type of Solar Thermal Collector which is made of Super Energy Heat Tube.  More information: Jetwen520@hotmail.com 

Thursday, October 30, 2008

Quantum Heat Pump Hot Water System



Automatic Solar Heating Controller



Our Solar Heater Controller is designed to automatically regulate the temperature of your swimming pool by controlling the flow of water through your solar panels.

On a hot day, the temperature of the water in the solar panel is warmer than the water in the swimming pool. The Controller unit will close the valve, which will cause the water to circulate through the solar panels. This will increase the pool water temperature up to the temperature that you set on the Controller.

 

On a cold or over cast day, the temperature of the water in the solar panel will be colder than the water in the swimming pool. The Controller unit will open the valve and the water will bypass the solar panel back in to the swimming pool, thus eliminating any loss of heat. 

Once the unit is installed and your ideal temperature set, the Controller unit will automatically open and close the valve as illustrated in the diagram. This will help keep your pool at a constant temperature all year round.



Tuesday, October 28, 2008

Closed-Loop Solar System



This is Closed-Loop Solar System but made of Super Energy Heat Tube. It is high efficiency and long life span. Easy installation and no Maintenance.
Super Energy Heat Tube just can be plug in or plug out manifold. Easier install than Heat Pipe.
More info,contact me: Jetwen520@hotmail.com  

Friday, October 3, 2008

The New Type of Evacuated Tube





1. No Water Inside Tube for Non-Pressurized Tank, The Condenser of Tube will plug into Non-Pressurized Tank directly to heat water. Because it is double sides closed.

2. No deposits Inside Tube, because it is two sides closed.

3. High Temperature Stagnation, No Tube Explosion.

4. 10% higher heat efficiency than common tube

5. Very good durability performance6. Strongly recommend to use in colder and hotter area


Working Principle of Super Heat Energy Collecting Tube:


There are some chemical media which can circulate from the bottom to the top inside of inner tube. The tube must be working in some angles. Otherwise it can not work. When the Tube collects heat from The Sun, liquid chemical media inside of tube is evaporating into gaseous state and gradually move to the top of tube(we called Condenser). But there are some temperature differences between Top and bottom of tube. Top’s temperature is lower than bottom’s. Then liquid chemical media in gaseous state meet lower temperature in condenser area and meanwhile lost heat. Finally it become liquid state and will slow down to the bottom. Then collecting heat from Sun, evaporate into gaseous state and Circulate again. As long as there is Sunshine, the circulation will work forever.
MSN/ E-mail: Jetwen520@hotmail.com
Skype: Jet_wen