According to technical experts, the first thing to consider when buying solar water heaters is the materials used in the products. Generally speaking, the service life of foam as heat insulation material of water heater is only 3 to 4 years, while polyurethane can be used for more than 15 years; Import and export nozzles and water storage tanks meet drinking standards, while the latter is the opposite. In addition, the service life of the product can be greatly prolonged by adopting the non-welding connection process of the water storage tank.
From the convenience of use, it is better to choose a product that can automatically add water and stop water and display the water level and water temperature, rather than buying a water heater that overflows when the water storage tank is full. If you want to use solar water heaters in rainy and snowy weather, you should buy photoelectric complementary products. ? Finally, it depends on the after-sales service of the products. It is best to choose products with quality insurance, because the vacuum tube of the water heater is made of high borosilicate hard glass, which has strong impact resistance, but it will still be damaged when encountering heavy hail. If the water heater you buy has quality insurance, timely compensation and good after-sales service, you will have no worries.
Simple selection judgment method
1, depending on the appearance (fineness of workmanship: treatment of water tank, bracket, screws and insulation materials)
2, look at the stent firmness (stent thickness), corrosion resistance (material), stability can also be weighed.
3. Thickness of water tank liner (weigh the water tank, which is a bit heavy for most people)
4, the color of the vacuum tube (single, all) whether there is color difference, whether consistent. You can also simply compare the weight of each solar vacuum tube for better focusing.
Price and cost analysis of solar cell modules in Sun Xia.
I. Materials needed by solar module
1. solar grade single (polycrystalline) battery
2. Tinned tape
3. Tempered glass
4.？ extravehicular activity
5.？ Test model
6. Flow
7. Solder wire
8. Isopropanol
9. Silica gel (silicone rubber sealant)
10. Junction box
1 1. aluminum frame
Second, the battery module monomer material analysis
1. Battery
( 1)? Usage: directly convert light energy into electric energy.
(2)? Materials: monocrystalline silicon battery, polycrystalline silicon battery.
(3)? Price factor: its cost accounts for more than 85% of the cost of a component.
2. Tinned tape:
Also known as: tinned copper tape/tinned welding tape/tinned alloy tape/tinned copper alloy tape/tinned welding wire/bus bar.
( 1)? Function: Tin-coated tape is used for series welding and confluence welding of solar cells in solar module production, which requires high welding operability and firmness.
(2)? Raw materials: Tin-coated tape is made of oxygen-free copper through shearing, drawing or rolling, with hot-dip coating on the outer surface.
A. Lead-free tinned tape? (Tin plating, silver plating, main material: copper. )? Environmental protection.
B. lead-tin tape? (Tin, lead hot plating, main material: copper. )
(3)? Price factor:
Affected by the prices of copper, tin, silver and lead.
Copper: At present, the futures price is around 55-60 yuan per kilogram, which has been rising.
Lead: At present, the futures price is about per kilogram 19 yuan, which has been on the rise.
3. Tempered glass? Low iron ultra-white calendered glass
Tempered glass is made of ordinary flat glass or float glass.
Tempered glass with a thickness of 3.2mm±0.3mm; Does the toughening performance meet the national standard: GB9963-88, or does the impact resistance of the packaging parts meet the national standard? GB9535-88？ Performance indicators specified in the environmental test method for ground silicon solar cell modules; In general, the light transmittance should be higher than 90%; The glass shall be clean and free of water vapor, and both sides of the glass shall not be touched by bare hands.
Ultra-white glass in photovoltaic cell modules has two main requirements:
A. strength:? When using and processing components, the glass should be resistant to temperature cycling, flat and pressure, and ultra-low self-explosion rate.
B light transmittance: the light transmittance is inversely proportional to the iron content, and the lower the iron content of glass, the better the light transmittance.
( 1)? Function: It plays a good role in protecting solar cells.
(2)? Material: a. float white glass
Production: Float glass is a transparent five-color flat glass made of sea sand, seasonal sandstone powder, soda ash and dolomite. According to a certain proportion, it is melted in the furnace at high temperature, and the glass liquid continuously flows out of the pool furnace to float on the metal surface, spreads into a glass ribbon with uniform thickness, is polished by fire, cooled and hardened, separated from the metal liquid, and then annealed and cut.
Features: the glass surface is particularly smooth, the thickness is very uniform, and the optical distortion is very small.
Classification: according to the appearance quality, it is divided into three categories: superior product, first-class product and qualified product.
According to the thickness, it can be divided into seven types: 3, 4, 5, 6, 8, 10 and12 mm.
4.？ extravehicular activity
(1) Function: a. Encapsulate the battery to prevent the external environment from affecting the electrical performance of the battery. ? Enhance the light transmittance of the assembly. ? C the battery, tempered glass and TPT are bonded together with a certain bonding strength.
(2)? Material: EVA is a copolymer of ethylene and vinyl acetate. It is a kind of hot melt adhesive, which is non-sticky at room temperature and convenient to operate. After hot pressing under certain conditions, melt bonding, cross-linking and curing will occur and become completely transparent.
(3) Price factor:
A. ethylene:
Affected by the trend of international crude oil prices, the prices of oil and ethylene rose sharply in 2007. Since June 2007, 65438+ 10, the average price of oil has remained at the level of 80-85 USD/barrel, which is about 50% higher than the same period in 2006, and the price of ethylene has also remained at the level of 1200 USD/ton. However, with the gradual stabilization of international oil prices, the prices of oil and ethylene are also expected to stabilize gradually. Expect? In 2008, the price of naphtha and ethylene will fluctuate greatly with the international crude oil price, which will affect the production of downstream enterprises.
The PE industry in China is also showing a trend of rapid growth. From 2004 to 2006, China's new PE production capacity was 3 1 10,000 tons/year,10.20 million tons/year and10.85 million tons/year respectively. At present, the PE production capacity in China is about100000 tons/year. The overall market price of polyethylene continues to rise, mainly driven by the increase in ex-factory price of domestic petrochemical enterprises; Second, the overall market resources are still in short supply.
B. vinyl acetate:? Its main raw material is also ethylene. Therefore, upstream products are still affected by crude oil prices.
Dow Chemical Company raised the price of vinyl acetate globally from June 5438+1 October12008. In Latin America, Middle East/Africa and Asia, the price was raised by USD 65,438+000/ton, EUR 65,438+000/ton in Europe and 5 cents/pound (USD 65,438+065,438+00/ton) in the United States and Canada.
Hysmans Chemical announced that it would raise the global price of acetate products. Due to the increase of raw materials, energy and freight, the new price will be implemented from June 65438+ 10/2008, or according to the contract price. The global price of ethyl acetate is planned to increase by 4 cents/pound ($88/ton).
* (Dow Chemical Company, 1897, founded in the United States, is a technology-based multinational company, ranking second in the world chemical industry (DuPont Company ranked first in the United States)).
Heismann Chemical Company is a global multinational company that produces and sells chemicals, fibers and plastics.
5.？ TPE？ /? TPT
TPE: thermoplastic elastomer with high elasticity and high recovery (thermoplastic? Elastomer) composites.
TPT: polyvinyl fluoride composite membrane
(1) Function: Both of them are structural packaging materials of solar cells and are used as substrates of solar cells.
A.？ It plays a good role in protecting the back of solar cells. It has the properties of aging resistance, corrosion resistance, solvent resistance, stain resistance, hydrophobicity, etc. Polyester has excellent mechanical properties, barrier performance and low water absorption, which can effectively prevent media, especially water, oxygen, corrosive gases and liquids (such as acid rain) from eroding EVA and affecting solar cells.
B.？ The fluoroplastic film is white and can reflect sunlight, so the efficiency of the module is slightly improved. Because of its high infrared emissivity, it can also reduce the working temperature of the module and help to improve the efficiency of the module.
(2) Price factor: There are no domestic manufacturers, so they need to buy from agents or import directly from abroad. So the price cost is relatively high.
6. Flux (wash-free, environmentally friendly)
(1) Function: It assists the series/parallel connection between the tin-coated tape and the positive and negative electrodes of the battery, so that after the battery panel circuit is welded, the solder joint has good luster, high strength, excellent conductivity, less residue after welding and no need for cleaning.
(2) Materials: organic solvent, rosin resin and its derivatives, synthetic resin surfactant, organic acid activator, corrosion inhibitor, cosolvent and film former. Simply put, it is to dissolve various solid components in various liquids to form a uniform and transparent mixed solution, in which different proportions of various components have different functions. ? The variety we bought: Kester: 920? CXF？ (Kester? 920CXF) imported, wash-free, environmentally friendly.
(3) Price factor: The products used have excellent performance and can guarantee good product quality. There are no domestic manufacturers, relying entirely on imports or distributors, so the price is higher.
7. Solder wire
( 1)? Function: Auxiliary series/parallel connection between tin-coated tape and battery anode and cathode.
(2)? Materials: tin and lead. The varieties we bought are: 60% tin and 40% lead (Sn60Pb40).
(3) Price factor: The price of this product is generally stable with little change, which will be slightly affected by the price level.
8. Isopropanol? IPA？ Isopropyl? alcohol
Appearance and personality:? Colorless and transparent liquid, smells like a mixture of ethanol and acetone. Colorless orange liquid. It is miscible with water, alcohol and ether. Its steam and air will form an explosive mixture. The allowable limit is 8% by volume. Toxic. First-class flammable liquid. Sealed and preserved. 150Kg barrel, which should be stored in a cool and ventilated special warehouse, far away from the fire source, and stored and transported according to the regulations of flammable chemicals.
Toxic. First-class flammable liquid. Sealed and preserved. 150Kg barrel, which should be stored in a cool and ventilated special warehouse, far away from the fire source, and stored and transported according to the regulations of flammable chemicals.
( 1)? Function: Used as cleaning agent for solar cells.
(2)? Materials: It is made from sulfuric acid and propylene through a series of chemical reactions.
(3) Price factor: Because the raw material of propylene is also crude oil, it is also affected by the international crude oil price trend. At present, Hysmans Chemical Company has raised the price of isopropanol worldwide from June 5438+ 10, 2008, with the range of 0.04 USD/lb (0.088 USD/kg). First, the average price of crude oil in 2008 will be higher than that in 2007, and the price of petrochemical products will be driven by cost. Second, the supply and demand of the industry can still be balanced. Although the growth rate of demand is slowing down, it is not significant, and the production capacity will increase rapidly. However, due to the withdrawal of backward production capacity, the effective production capacity may not be greatly expanded, so the relationship between supply and demand can basically be balanced.
9. Silicone rubber sealant
( 1)? Function: Silicone rubber sealant products are suitable for bonding/sealing ultraviolet-resistant insulating glass and solar panels.
In order to manufacture solar cell modules, silica gel materials are usually used in three places:
A. silica gel for sealing aluminum alloy frame
B. The junction box is fixed on the back of the battery panel and bonded with silica gel.
C. Some junction boxes are sealed with thermally conductive silicone materials.
(2)? Material: General requirements of silica gel:
A. comply with the ROHS environmental protection certification of the European Union.
B. Meet UL fire protection certification
C. Anti-aging: 85 degrees, 85% humidity, 1000 hour anti-aging experiment.
D-40 ~ 85 high and low temperature experiment, 200 cycles, 30 minutes per cycle.
Domestic representative products:
A. Dow corning? 709 1
B. Beijing kesaixin? 1527 (Tianshan Mountain)
C. Shanghai returns to heaven? 906
D. shinetsu KE45
At present, some problems existing in silica gel:
A. incomplete certification (because more products have been exported)
B.the price is very high
C part of silica gel reacts with EVA in the battery module and turns yellow.
D. Some silica gels can't meet the requirements in weather resistance, aging resistance and ultraviolet resistance, so it is difficult to use for 20 years.
The above requirements.
(3) Price factor: The raw materials for preparing silicone oil, silicone rubber, silicone resin and silane coupling agent are various silicone monomers, and several basic monomers can produce thousands of silicone products. Silicone monomers mainly include methyl chlorosilane (methyl monomer), phenyl chlorosilane (phenyl monomer), methyl vinyl chlorosilane, ethyl trichlorosilane, propyl trichlorosilane, vinyl trichlorosilane, γ-chloropropyl trichlorosilane and fluorosilicone monomer. Among them, methyl chlorosilane is the most important, accounting for more than 90% of the total monomer, followed by phenyl chlorosilane.
The raw material of the above-mentioned silicone monomer comes from petroleum, so the price of this product is still affected by the price of crude oil.
10. Junction box-Two-component silicone heat conductive potting compound
( 1)? Function: Weld a box at the lead on the back of the module to facilitate the connection between the battery and other equipment or batteries.
(2)? Material: Two-component silicone heat-conducting potting compound: a heat-conducting insulating material, which requires no heat release, no corrosion and small shrinkage when cured. It is suitable for sealing and pouring with various heat-conducting electronic components to form a heat-conducting insulation system. Its characteristics are: a. room temperature curing, rapid curing by heating, and convenient use; ? B, keeping rubber elasticity in a wide temperature range (-60℃-250℃), having excellent electrical properties, very small dielectric constant and dielectric loss, and good thermal conductivity; C waterproof and moistureproof, resistant to chemical media and weathering for more than 25 years; D. Good adhesion with most plastics, rubber, nylon, polyphenylene ether, PPO and other materials; ? E meet the requirements of ROHS environmental protection directive of the European union.
(3) Price factor: The price of this product is generally stable with little change, which will be slightly affected by the price level. The price is mainly determined by the performance of the product itself.
1 1.？ Aluminum alloy frame
( 1)? Function: a. Protect the glass edge? B aluminum alloy combined with silica gel wrapping enhances the sealing performance of the module? C. greatly improve the mechanical strength of the whole assembly? D. facilitate the installation and transportation of components.
(2)? Material: A. The metal frame of the module is made of aluminum alloy. In order to meet the mechanical strength requirements of photovoltaic modules, refer to GB/T3 190— 1996 Chemical Composition of Wrought Aluminum and Aluminum Alloys, and adopt the international general brand 6063T6 aluminum alloy. B. In order to ensure the service life of solar module for 25 years, the surface of aluminum alloy must be passivated-anodized, and the thickness of the surface oxide layer is greater than10 μ m. The frame used for packaging should be free from deformation and scratches.
(3) Price factor: mainly affected by aluminum price. At present, the futures price of non-ferrous aluminum is about 17 yuan/kg. In July 2006, the price of aluminum was about 19 yuan/kg (19000 yuan/ton).
Sangxia solar water heater price
Sancha q-b-j-1-140/2.39/0.05? Product reference price 3 180
Sancha q-b-j-1-185/3.20/0.05? Product reference price 3680
Sangxia q-b-j-1-140/2.10/0.05? Product reference price 2960
Sancha q-b-j-1-245/4.05438+0/0.05? Product reference price 3990
Sancha q-b-j-1-125/2.23/0.05? Product reference price 2580