What Kind of Distributed Solar Photovoltaic Roof are Most Valuable

" Solar PV power industry next era should be called 'pro-roof resource is the king'." Co-director of Hangyu Technology Co., Ltd. (hereinafter referred to as Hangyu energy) Yang Liu believes that the scarcity of resources is the pain point of industry development, who will occupy the first chance who can solve it, and the future PV market will not lack of polysilicon, nor photovoltaic modules, but the roof. 

His judgment is based on an industry consensus: China's distributed solar PV market is heating up. The so-called distributed photovoltaic, usually refers to small-scale photovoltaic power generation system( off grid solar power system) is installed in home or residential commercial and industrial rooftops, courtyards, to the owners of self-occupied, remaining electricity access to the grid operation. In the photovoltaic market started earlier in Europe and America, it is the main way of distributed photovoltaic solar energy utilization. Nearly nine out of Germany from distributed solar photovoltaic power generation system, the number of family homes roof power plant over one million; Last year the United States added new distributed photovoltaic power generation capacity has reached 2.2 million kilowatts.

In China, large-scale centralized ground station is still the main way to achieve solar photovoltaic power generation. Up to 2014, China PV cumulative installed capacity of 28.05 million kilowatts grid. Among them, the ground station are 23.38 million kilowatts, only 4.67 million kilowatts of photovoltaic distributed. However, in view of land resources, the ability to send power grids and national subsidy financial pressure and many other constraints, many people in the industry have expressed similar views to the author, that the development of the ground station will gradually slow down over next three years, and various distributions the formula will be the development direction.

 

"From an investment point of view, the ground station can last two or three years." In the GCL New Energy Holdings Limited (00451.HK, hereinafter referred to as GCL new energy) in the photovoltaic power generation project investment Shanzhong Zhang think that, PV application market the determining factor is financial leverage. "It is a hot point of ground station, at their own expense by 10%, someone take 90% to capital. Although distributed project now unable to do, all the bad factors will improve over time. We look for the market will be forced to the roof.

With more and more enterprises and funds investing in distributed solar photovoltaic, roof, especially those who are most power and profit potential high quality roof, just as land is becoming parties to compete for the subject. But what kind of roofs are most valuable?

 

Big business Roofs are rarest

Since human Jielu to live, the roof is not new things, but people take it from the photovoltaic various grades and ranks

"Duddy, I have roof resources, let's look at?" this is Yang Liu the most afraid to hear words, because many people mistakenly think that the "roof" is equal to "project". And for professionals, choose roof as like choose beauty.

Economy is the primary criterion for evaluation rooftop PV projects. Roof, whose owners units best are the stable operation and strong big power to the roof. High energy consuming owners to install distributed solar off grid system, to achieve to  maximize the economic benefits of the project. National policy to encourage power users in accordance with the "spontaneous use, grid allowance" approach to building distributed photovoltaic power generation system. The NDRC price department 2013 No. 1638 documents stipulate, to distributed photovoltaic generating electricity subsidies policy, subsidies standard is RMB 0.42 per kilowatt hour; Among them, occupied the remaining power grid, by the power grid enterprises in accordance with the local coal-fired units benchmarking Internet acquisition price.

If business owners can use all photovoltaic self-occupied, it will be the largest economic investment. Because according to the current policy, self-occupied part of the earnings-per-watt is equal to the original unit price of electricity plus state subsidies RMB 0.42, while the online portion of the earnings power more than just benchmark electricity price increase state subsidies, currently around commercial and industrial electricity prices are far higher in feed-in tariffs.

But the scale of development is another important index to distinguish the quality of the roof. The scale 1 MW project compared with 5 MW project, two pre development costs are basically the same, investors certainly love big roof project.

Different Geographical position can also delete a large part of the roof. PowerOAK family photovoltaic a person in charge told reporters, the current domestic suitable for large-scale development of distributed PV provinces are rarely, one is in the provinces of Shanghai, Zhejiang and other places have high subsidies; the other is the local power supply tension leads to commercial and industrial electricity prices high provinces, such as Guangdong.

Therefore, in the eyes of distributed PV developers high quality roof need to contain the following characteristics: owners stable operation and high power consumption; long period existence of roof; suitable for developing more than 5 MW large roof solar power station; high local subsidies or local industry and commercial with high price. Accord with above standard of roof resources are very scarce. "Most of the best roof are state-owned enterprises, central enterprises and large listed companies, small private enterprises dare to guarantee stable operation of 20 years is not much, not to mention the meeting other conditions." an investment industry sources to the author said.

The roof of various grades and ranks

Small area roofs, solar photovoltaic power generation can provide attractive business owners inherently inadequate. These roofs can try to re-rent pack make up large projects. PowerOAK is doing that.

From the perspective of the economic benefits investment, the small scale roof still does not have the attraction. For example, IKEA Beijing Quaternion Bridge shop which roof power station the annual average generating capacity are about 30 million degrees, barely enough to meet the market 80% lighting power supply system, the entire Mall consumption is a drop in the bucket. But similar like IKEA companies test photovoltaic roof, even more to see solar PV power as a green energy behind the concept of environmental protection, which to boost corporate influence, shaping a good social image have a positive effect.

There are some people in the industry believe that only a small rooftop distributed PV on behalf of the trend of development. Yang Liu predicted that, in five years distributed PV market will be hot competition for resources roof scale 1 MW or less.

This judgment from foreign experience in the development of photovoltaic PV market, has always been from easy to difficult, from the depth of large-scale to small-scale distributed . But China’s situation is different, the small roof era needs more time. The current trend is visible from the scale effect was significantly depleted but soon developed a large-scale ground station resources to the same large-scale distributed projects. To distributed project about large-scale agricultural photovoltaic project Zhang Shanzhong told the author that large-scale agriculture, fishery and photovoltaic complementary projects, can extend large-scale ground station investment heat 1-2 years. Such projects currently classified as distributed, but its construction business model and business investment model and the large ground station is not very different, are the grid, with full electricity sold to the grid, obtained subsidized price revenue. This kind of distributed project business model are relatively mature, easy to attract investment. 

China's Solar Photovoltaic Products and Grid Standards will Double Upgrade

According to the different development stages of solar photovoltaic power technology and products, adopt different market access standards; take not mandatory for optical fiber communication, does not require the low voltage ride through or require the grid to detect simplified grid measures to ensure the smooth distributed photovoltaic grid. In June, the photovoltaic industry new policy taken place frequently, targeting the overall industrial technology upgrade slowly, the development of grid technical standard missing. Recently, the National Energy Bureau, Ministry of industry and information technology, CNCA jointly issued "About the promotion of solar photovoltaic products advanced technology application and industrial upgrading opinions (hereinafter referred to as the" opinions "). In addition, the project of “ Research on key technical standards for grid connected photovoltaic power generation”in early 6 has been acceptance inspection. From the two aspects of the manufacture and application of the market, photovoltaic technology products and power grid access standards in China will double upgrade.

"China's photovoltaic industry scale ranks first in the world, behind this aura rely on the size of benefit, rather than technical and quality benefits. If the PV industry in China is still playing 'world's factory' role, the road will be unsustainable in the future. "China renewable energy Society of vice president Meng Xiangan in an interview with the author said that, China's photovoltaic technology and industrial product applications urgent need to upgrade, this is a" must do it "thing. The PV market access standards for circulation of progressive mechanism, which means it will be a continuous and long-term photovoltaic industry knockout.

The first round standards are not high and will be circulation in the future

In the photovoltaic market access standards, "opinions" on the photoelectric conversion efficiency and the decay rate of two indicators put forward the quantitative criteria. Among them, the solar photovoltaic power generation projects newly purchased PV modules should meet the Ministry of Industry and Information Technology "PV manufacturing industry norm conditions" (2015 present) Related products technical requirements, such as photoelectric conversion efficiency of polycrystalline silicon cells and battery pack assembly, respectively not less than 15.5% and 16%,HCPV module photoelectric conversion efficiency is not less than 28%.

Data show that, currently China's large-scale industrial production of monocrystalline silicon cell photovoltaic conversion efficiency are about 19%, the photoelectric conversion efficiency of polycrystalline silicon cells are about 18%. "The decline in the conversion efficiency of the battery components based on the data were about 2 percentage points. Not difficult to see," Opinions "put forward by the first round of 'threshold' is not high, China's photovoltaic manufacturing enterprises are generally reached standard." Mengxian Gan said.

In order to further improve the relevant enterprises to establish awareness of the technology advantages, < Opinion> also clear, National Energy Bureau each year will arrange size of specialized market plans to implement the "leader", requirements for the use of advanced technology products in the project. It is reported that the "leader" plan requirement on advanced technology products more high, such as the photoelectric conversion efficiency of polycrystalline silicon solar cell components and monocrystalline silicon solar cells components reached 16.5% and 17%.

"As like the currently China to boost distributed solar off grid system applications in advance demonstration area, to carry out the 'leader' program, and more higher demands for its technology products, to a certain extent, is to give the latest PV technologies and business models to establish use Referring to the benchmark, accelerate backward production capacity out of the market , advanced technology products to market faster, and promote the photovoltaic industry overall rapid technological upgrading. "Mengxian Gan said.

It is worth noting that, "opinions” is put forward in the standard photovoltaic products market access at the same time, also attached a sentence: the index will be adjusted according to the industrial development.

"Gradually establish a market access standards for PV cycle progression mechanisms, photovoltaic technology will accelerate progress and industrial upgrading." Mengxian Gan pointed out, according to the different stages of the development of photovoltaic technology and products, adopt differentiated market access standards, will support in favor of advanced technology products to expand the market, accelerate the elimination of backward technology products, standardize photovoltaic technology and quality supervision management. According to his analysis, the next photoelectric conversion efficiency of polycrystalline silicon and monocrystalline silicon modules battery components market access standards will increase 0.3% to 0.5% per year.

PV grid standard system to speed up the improvement process

Upstream and photovoltaic manufacturing photovoltaic products due to technological upgrading slow, and lack of core competitiveness in international markets, like photovoltaic applications for domestic market, the lack of grid standards, has become the main obstacle to promote its further development.

Grid technology standards is to protect the photovoltaic grid connected reliably, the foundation of safe and stable operation and high consumptive. I understand that, on June 3, "study on key of technical standards for grid connected photovoltaic power generation” project through acceptance. This means that, to improve the standard of the photovoltaic power generation system will be set up in China, for China on grid solar power system plant construction, acceptance, operation and maintenance to provide comprehensive guidance.

Participation and commitment of the project research China EPRI Guoqing, deputy director of the Energy Research Institute in New interview with this reporter, said, "PV gateway and key technical standards study" by the China Electricity Council, led the project to build of China's photovoltaic power generation and network standards framework, including universal basis, survey and design, construction inspection and quality assessment, maintenance and operation of the network and detect four broad categories of more than 80 criteria. The project also developed in line with China's national conditions of the photovoltaic power generation and grid national standards 13, 11 industry standards, have been published or submitted for approval.

Guoqing He told the author, for large terrestrial photovoltaic power plant,the grid characteristics and wind have a lot in common, so the formulation of the standard photovoltaic power station to make full use of the experience and lessons of the wind turbine standards, < photovoltaic power station is connected to the electric power system technology regulations > in the active power change rate, low voltage ride through (LVRT), grid adaptation, with the same also different, highlighting the photovoltaic short-time power changes faster, the inverter control performance is better. 

"With the wind power mainly centralized development is different, photovoltaic power generation market have a large number of distributed development ways, because of the distributed development over a broad area, a single small capacity, less investment, high standard grid will greatly increase the cost of grid. “The provisions on the access distribution network technology” said for distributed took not mandatory for the optical fiber communication, does not require low the voltage crossing, does not require the grid detection measures to protect the simplified grid, distributed photovoltaic grid connected smoothly." Guoqing He introduced. According to the information monitoring, because don’t require distributed optical fiber communication network on the volt, brings great difficulties to the development of distributed PV grid monitoring, currently distributed PV are unpredictable, not monitoring, uncontrollable state. When the distributed solar PV power capacity reaches a certain proportion in certain areas, will be running on the grid with a greater risk.

"To this end, we have launched a distributed photovoltaic power grid control technology research and operational forecasting, a subregional, meshed manner distributed photovoltaic forecasting and monitoring, it can achieve one time 15 minutes of running information collection and storage , greatly improve the controllability of distributed PV understood. "He Guoqing said that, at present the technology has been in Beijing and Jiangsu have demonstration application, after further maturation can be applied across the country, not only help to improve the running stability of the grid, further It can be used to assess the quality of supervision and photovoltaic technologies.

Posted by Sarah Hwong, Mar.1,2016

The Characteristics Of Home Distributed Solar Power Plant

Distributed home solar power plant usually refers to the use of distributed resources, installed a smaller scale and arranged power system in their own home, it generally access below 35 kV or lower voltage level of power grid. Distributed solar photovoltaic power station refers to the use of photovoltaic modules, the direct conversion of solar energy into electrical energy distributed photovoltaic power system. Understanding distributed home solar power plant characteristics are more helpful for us to its overall control.

The characteristics of home distributed solar power plant:
　　
1. Output power is relatively small. The traditional centralized power plants frequently several hundreds of thousands kilowatts, or even millions kilowatts, large-scale application improve the economic. The modular design of solar off grid system photovoltaic power generation determines the the scale can be big or small, according to the capacity of the venue for adjusting the photovoltaic system. Generally, the capacity of a distributed solar photovoltaic power plant project is within thousands kilowatts. Unlike centralized solar power plants, the size of the photovoltaic power station has very little effect on the efficiency of electric power generation, so the economic effect is also very small, the rate of return on investment of small solar PV systems are no than lower the larges’.

2. Little pollution, environmental benefits outstanding. Distributed solar photovoltaic power plant project in the power generation process, there is no noise or nor to air and water produce pollution. However, it need to pay attention to harmonious development of distributed solar PV with the surrounding urban environment, in using clean energy, considering the public concern about the beauty of the city environment.

3. To a certain extent, ease the power shortage in the local situation. Distributed solar PV power plant output maximum in the daytime, just at this time the greatest demand for electricity. However, the energy density of distributed solar PV power plant is relatively low, the power per square meter of distributed solar PV power plant system is only about 100 watts, plus the installation of the PV modules for limiting in the roof area of the building, so the distributed solar photovoltaic power plants can not be fundamentally solved the power shortage problem.

Posted by Sarah Hwong,Feb.24,2016

Solar Power System Have A Unique Style Of Business Management

Nowadays,to install household solar power system to supply have been many foreign family intention to choose, but there is still exist large problem , initial installation cost is too high, so that many families can not be expected. Therefore, if we can reduce the cost of initial investment, there will be more family can be more easily used on solar power generation system. And in foreign countries, operating a solar photovoltaic power generation company launched a unique way to attract customers.

The company have engaged in the sale of solar power system more than three years, they always have been looking for more scheme selections for customers to accept, such as produce the small device—portable solar generator, but the final choice way is a lease. This way allow home users advance payment some rent then can use their products, and they can also charge a fee from the system maintenance and repair work.

From the operator's point of view, using the lease can attract more users , can rapidly increase the turnover ,to occupy the market rapidly. While from the user's point of view, first of all, they can pay the lowest of one-time inputs cost to use solar power system, don't worry about the daily maintenance and repair work; Secondly, because of the power buy back policy, the electricity generated can sell to the public grid, you can also earn some electric charge. Therefore this mode of operation by the users are welcome.

However, the biggest problem is requires large capital investment, that is to say, should have been borne by the user of the high initial cost to the operator. So it is necessary to have strong financial strength is likely to be used in such a way to operate, there is no doubt that this is a helpful to more families use solar power system model. From all solar photovoltaic power generation market , it is more and more popular to install solar off grid system at the roof ,perhaps this will bring large consortium entered.

Solar off grid power system Maintenance

“How many years can be used for solar off grid power system?”some new users often asked .I think this question should be separated, because one set completed solar power system include three parts: solar panel ,controller and inverter, battery.

Solar panel have a long service life, can reach 20-25 years; the same as controller and inverter can also reach 5-8 years, while the battery is just 3-5 years. As the battery energy storage device, is one of the most important part of solar off grid power system, but also the most vulnerable part , which lifespan directly determines solar power system's service life. Users in the use of solar off grid power system, special attention should be paid to maintenance of storage battery and inverter, these two components are affected by user habits. So should be pay attention to using.

First, battery maintenance

Batteries are experienced to repeat charging and discharging in the using process, the so-called battery lifespan, can be generally considered to be capable of withstanding charge and discharge cycle back number. The cycle back number first is affected by the depth of discharge, the deeper the depth of discharge, the few cycle back number will be. Secondly, if the battery is not timely charge after discharge, greatly reduced cycle times,too. So when in use, try to avoid excessive depth of discharge, if due to poor weather conditions, resulting in insufficient charge, you should use less or stop using. Especially in anticipation of a long rainy weather, must ensure the battery being a certain amount of power. That is to say, if want your off grid solar system have a long service life, need to protect the battery.

Second, inverter maintenance

Inverters have its rated output capacity, different capacity power generation system will configure different output capacity inverter. To power supply for home appliances, we must ensure that the electrical power is less than the inverter rating output capacity. Generally speaking, keep the electrical power is low in 80% of the power inverter is appropriate. For example, a 300W of off solar power system. The configuration of inverter is 1000W output capacity, can only give below the 1000W power electronics use , to make sure electrical power less than 800W will be the most reasonable. If it is inductive load motor, it should be below 200W.

It can be known ,the service life of solar off grid system m is affected by the user's habits, it need to be pay special attention to when using.