1.节能减排

如果采用燃煤发电，需要消耗宝贵的煤炭资源，同时产生大量的二氧化碳、二氧化硫、氮氧化物等，对生态环境造成破坏。

根据华电集团、国家电投集团、国家能源集团三家大型电力企业2019年供电煤耗情况计算得出，每发出1kWh电力，大约需要燃烧301g标准煤。

以光伏发电替代燃煤发电后，根据国家能源局统计数据，2019年全国光伏发电量达2243亿千瓦时，相当于节省标准煤6751.43万吨，同时减少二氧化碳排放1.9亿吨、二氧化硫排放118.28万吨、氮氧化物排放37.15万吨，并减少粉尘排放46.44万吨。

 2.防风固沙、植被恢复

 根据甘肃省治沙研究所的相关研究，沙漠、戈壁光伏产业对于防沙治沙具有十分显著的生态功能，其对于防沙治沙的生态功能主要表现在：

一是转化太阳辐射、调节沙漠、戈壁的热力平衡，削弱沙尘暴和大风；二是风障功能和沙障功能；三是集雨促进植物生长。发展沙漠、戈壁光伏产业，不仅具有显著的经济效益，而且具有防沙治沙的生态功能。我国沙漠、戈壁面积广大，发展沙漠、戈壁光伏产业前景广阔。沙漠、戈壁光伏产业可望成为继造林治沙、沙障压沙之后的第三条防沙治沙新途径。

已有的各种防沙治沙措施中，植物治沙是其中最理想的措施，然而，沙漠地区一般降水稀少，水资源缺乏，许多地区多年平均降水量低于200mm，远远小于蒸发量，不能满足造林治沙对水分的需要。换言之，如此低的降水量只能供给很稀疏的植被存活，而低盖度的植被对防沙固沙的作用是相当有限的。因此，光伏有利于转化太阳能，调节沙漠、戈壁的热力平衡。

关于光伏系统的集雨功能，甘肃省治沙研究所介绍，雨水降落到光伏板后即会沿倾斜板面向下落到光伏板面下沿地面，使得光伏板下沿地面80cm宽的范围内土壤含水率提高30%～60%，亦即光伏板形成了集雨面。光伏板倾斜边下沿地面不仅植物密度大，植株高，而且植物多样性也有明显增加。对4个光伏电站的调查结果显示，光伏电场内的植株高度平均为18.2cm，较光伏电场外围高6.4cm；植物盖度平均增加16.62%，较光伏电场外围高9.6%；植被投影盖度平均为10.3%，较光伏电场外高7.0% ；植物种类平均有7.1种，较光伏电场外围多3.6种。

此外，清洗光伏板的废水也可以促进光伏电场内的植被生长。在西北沙漠、戈壁地区，降水稀少，气候干燥，利用光伏板集雨功能和清洗光伏板的废水，对于促进植物生长、增加植被盖度和保护光伏电站具有重要意义。

光伏环境影响案例

 1.青海共和项目

共和县塔拉滩地区，是黄河上游和三江源地区风沙危害最严重的地区之一，总面积443.72万亩。近几十年来，由于受全球气候变暖、降水量减少、风沙危害等因素影响，塔拉滩土地沙漠化加剧，严重沙漠化土地以每年1.8万亩的速度增长，使该地区草场沙化面积达101.11万亩，每年进入龙羊峡库区流沙达3131万方，每年造成经济损失逾4600万元。

这种局面自2011年起开始逐步得到了改变。从2011年到2017年，40多家光伏企业累计投资建设光伏电站约3350MW，其中国家电投黄河水电建设1725MW，占据了半壁江山。

从2014年开始，黄河水电开始在光伏园区周围撒下了牧草草种，一来为了恢复生态，二来是为了减少风沙对光伏发电量的影响。一年后，园区周围的荒漠化土地有了好转，原本退化明显的草场长满了牧草，甚至需要人工割草才能避免草木遮挡组件。为此，光伏企业开始雇佣当地牧民养羊放牧，昔日的茫茫戈壁“变身”为草原牧场。监测数据表明，光伏电站的建设使子阵区域内的风速和晴天天气下蒸发量都平均降低50%以上，草原的含水量大大增加，在有利于遏制土地荒漠化同时，植被形成的绿色屏障还能改善光伏电站周边环境，降低风沙对光伏电站发电量造成的损失，实现了“双赢”。

 2.内蒙古库布齐光伏治沙项目

库布齐沙漠地处内蒙古自治区鄂尔多斯市杭锦旗，是中国第七大沙漠，也是距离北京最近的沙漠，曾是北京及周边地区沙尘暴的主要来源。针对库布齐的治沙研究，早在上个世纪五十年代就已经展开，但多年来一直未有明显的治理成效。

直到2011年，内蒙古亿利资源集团和正泰集团的“沙光互补”项目在此动工，库布齐的沙漠治理终于走上正轨。

据了解，库布其沙漠每年的光照时间达到3180小时以上，太阳能资源非常丰富。2018年，库布齐光伏电站项目发电量超过5.5亿千瓦时，相当于节约标准煤约10.33万吨，减少二氧化碳排放约28.61万吨，减少二氧化硫排放约9390吨，减少氮氧化物排放约4695吨，减少粉尘排放约8.5万吨，节约用水56.34万吨，提高可再生能源比例达2%。

根据相关专家测算，有了光伏组件和下方植物，当地每年可减少水分蒸发量800毫米，可以保留更多的地下水，有利于植物的存活和生长。此外，光伏系统可降低风速1.5米/秒。当地村民也透露，有时天气预报风力五到六级，光伏场区风力只有二到三级。

除了发电，库布齐光伏电站还成为了当地的扶贫项目，带动一部分农民成功脱贫。电站项目负责人徐胜虎介绍，通过流转租用农民土地，他们总共帮扶了800多户贫困户。此外，还聘用了57户贫困户到电站工作，每户贫困户的年收入可以达到3.5万元。

1. Energy conservation and emission reduction  

 

If coal-fired power generation is adopted, precious coal resources need to be consumed, while a large amount of carbon dioxide, sulfur dioxide, nitrogen oxide, etc., will be produced, causing damage to the ecological environment.  

 

According to the calculation of the coal consumption of power supply of Huadian Group, State Power Investment Group and State Energy Group in 2019, for every 1kWh power generation, about 301g standard coal needs to be burned.  

 

After replacing coal-fired power with photovoltaic power generation, according to the statistics of the National Energy Administration, in 2019, the photovoltaic power generation in China reached 224.3 billion KWH, equivalent to saving 67.514,300 tons of standard coal, and reducing carbon dioxide emissions by 190 million tons, sulfur dioxide emissions by 1.182,800 tons, and nitrogen oxide emissions by 371,500 tons.   And reduce dust emissions by 464,400 tons.  

 

2. Windbreak and sand fixation, vegetation restoration  

 

According to the relevant research of Gansu Desert Control Research Institute, the desert and Gobi photovoltaic industry has a very significant ecological function for desertification control, and its ecological function for desertification control is mainly reflected in:  

 

First, to transform solar radiation, adjust the thermal balance of deserts and Gobi, and weaken dust storms and gales;  The second is the function of wind barrier and sand barrier;  Third, rainwater collection promotes plant growth.  The development of desert, Gobi photovoltaic industry, not only has significant economic benefits, but also has the ecological function of desertification prevention and control.  China's desert, Gobi area is broad, the development of desert, Gobi photovoltaic industry has broad prospects.  The photovoltaic industry in desert and Gobi is expected to become the third new way to control sand after afforestation and sand barrier.  

 

Among all kinds of existing measures for desertification control, plant desertification control is the most ideal one. However, desert areas generally have scarce precipitation and lack of water resources. In many areas, the average annual precipitation is less than 200mm, far less than evaporation, which cannot meet the water needs of afforestation and desertification control.   In other words, such low precipitation can only provide very sparse vegetation to survive, and the low coverage of vegetation on sand control and fixation is rather limited.   Therefore, photovoltaic is conducive to the conversion of solar energy, adjust the thermal balance of desert, Gobi.  

 

As for the rainwater catching function of the photovoltaic system, Gansu Province Sand Control Research Institute introduced that after the rain falls to the photovoltaic panel, it will fall down to the surface of the photovoltaic panel along the ground, making the soil moisture content of the photovoltaic panel along the ground 80cm wide range increased by 30% to 60%, that is, the photovoltaic panel formed a rainwater catching surface.   Not only the density of plants along the ground under the tilted edge of the photovoltaic panel is high, but also the plant diversity is significantly increased.  The survey results of four photovoltaic power plants showed that the average height of plants in the photovoltaic field was 18.2cm, which was 6.4cm higher than that in the outside of the photovoltaic power plant.  The plant coverage increased by 16.62% on average, which was 9.6% higher than that in the periphery of the photovoltaic electric field.  The vegetation projection coverage was 10.3% on average, which was 7.0% higher than that of the photovoltaic site.  The average number of plant species was 7.1, 3.6 more than that in the periphery of the photovoltaic electric field.  

 

In addition, the wastewater from cleaning the PV panels can also promote the growth of vegetation in the PV field.  In the Northwest desert and Gobi region, where precipitation is rare and the climate is dry, it is of great significance to use the rainwater harvesting function of photovoltaic panels and clean the wastewater of photovoltaic panels to promote plant growth, increase vegetation coverage and protect photovoltaic power stations.  

 

Pv Environmental impact case  

 

1. Qinghai Republic Project  

 

The TALATAN AREA OF GONGHE COUNTY IS one of THE most SERIOUS AREAS IN the upper reaches of the Yellow River and the source of the three RIVERS, with a total area of 4.4372 million mu.   In recent decades, due to global warming, precipitation decrease, influence factors, such as sand dunes hazard, tara beach land desertification, serious desertification land rising at an annual rate of 18000 mu, the region grassland desertification area of 1.0111 million mu, a year into the results of the quicksand of 31.31 million square, causing economic losses of more than 46 million yuan a year.  

 

This situation has gradually begun to change since 2011.  From 2011 to 2017, more than 40 photovoltaic enterprises have invested in the construction of about 3,350 MW of photovoltaic power stations, among which the State Power Investment Yellow River hydropower construction 1,725 MW, accounting for half of the country.  

 

Since 2014, Yellow River Hydropower Corporation has sown grass seeds around the photovoltaic park to restore ecology and reduce the impact of wind and sand on photovoltaic power generation.  A year later, the desertification land around the park has improved. The degraded grassland has been overgrown with grass, and even manual mowing is needed to avoid vegetation blocking components.   To this end, photovoltaic enterprises began to hire local herdsmen to raise sheep grazing, the former vast Gobi "transformed" into grassland pastures.   Monitoring data show that in the construction of the photovoltaic power station makes the submatrix area average wind speed and evaporation under sunny weather is reduced by more than 50%, greatly increase the water content of the prairie, while beneficial to curb desertification, vegetation formation of green barriers can also improve the photovoltaic power station environment, reduce the loss caused by sand on photovoltaic power generation, to achieve the "win-win".  

 

2. Inner Mongolia Kubuqi Photovoltaic sand Control Project  

 

Located in Hangjin Banner, Ordos City, Inner Mongolia Autonomous Region, the Kubuqi Desert is the seventh largest desert in China and the closest to Beijing. It used to be the main source of sandstorms in Beijing and surrounding areas.   The research on sand control in Kubuqi has been carried out as early as the 1950s of last century, but there has been no obvious effect for many years.  

 

It was not until 2011 that Inner Mongolia Yili Resources Group and Chint Group started construction of the "sand and Light Complementing" project, which finally put Kubuqi's desert governance on the right track.  

 

It is understood that the annual illumination time of Kubuqi desert reaches more than 3180 hours, and the solar energy resources are very rich.   In 2018, the Kubuqi photovoltaic power Station project generated more than 550 million KWH of electricity, equivalent to saving about 103,300 tons of standard coal, 286,100 tons of carbon dioxide emissions, 9,390 tons of sulfur dioxide emissions, 4,695 tons of nitrogen oxide emissions, 85,000 tons of dust emissions, and 563,400 tons of water.  Increase the share of renewable energy to 2%.  

 

According to the calculation of relevant experts, with the photovoltaic module and the plants below, the local water evaporation can be reduced by 800 mm per year, and more groundwater can be retained, which is conducive to the survival and growth of plants.   In addition, the PV system can reduce wind speed by 1.5 m/s.  Local villagers also revealed that sometimes the weather forecast wind power five to six, photovoltaic field area only two to three wind.  

 

In addition to generating electricity, the Kubuqi photovoltaic power station has also become a local poverty alleviation project, which has helped some farmers to lift themselves out of poverty.   Xu Shenghu, head of the power plant project, said they had helped more than 800 poor households by transferring leased land from farmers.  In addition, 57 poor households have been hired to work at the plant, with each household earning 35,000 yuan a year.