Projects recommendation: desert control & pumping trickle irrigation system for highway

1. Situation

Introduction: China economy is in rapid development at the same time also faces

enormous environmental challenges. The northern desert is one of many issues. Most

northern areas of China are in desertification, serious desertification affects not only the

transportation line running stability and normal usage period, but also has the serious

influence to the environment of the surrounding areas especially Beijing.

The local government hopes that our company could help them with prevention and cure

of desertification, to create a ' Green Barrier ' which is a shelter forest to stop sands

expansion for human and economic activity in Beijing and northern areas.

In order to prevent wind erosion on highway, grass grids are usually used to ensure the

highway runs well at the initial completion stage. Such a project needs a lot of time and

labour, it costs extremely high. Therefore, creating a permanent forest along the highway

is the preferred choice,

Shenzhen Solartech Renewable Energy is a professional solar pumping system and

solar grid-connected system manufacturer, handling R&D, production as well as sales.

Doctor Xuzhen, our chief engineer , helped the government to design and create a solar

water pumping system for highway desertification protection in Hade district of Xinjiang

province in 2001. The system has been running steadily more than 10 years already. The

successful experience has proved that our system can completely meet the requirements

of forest creating along the highway in the desert, but without any pollution.

2. System

A Solartech solar water pumping system mainly consists of PV array, solar water pump

inverter and 3 phase AC pump, easy for use. In order to reduce the construction and

operation cost, to improve the reliability of the system, the system rejects storage battery

which could cause serious pollution to environment, storing water instead of electricity,

reducing the construction cost and maintenance cost.

Independent solar pumping system has a bright future in solving the remote areas of

drinking water for people and livestock, agriculture and forest irrigation. For an AC

electric motor driven pump, it requires an inverter to convert DC output by PV array into

three-phase AC. With MPPT application, adjust output frequency in real time according to

light intensity, to guarantee maximum output power. The system has the advantages of

simple structure, high reliability, good dynamic characteristic, low cost. So far, there have

been no similar products at home and abroad, our technology has already taken the

leading position in the world

Combination

a. PV array

The power source for system made of photovoltaic modules in series-parallel, absorbing

solar radiation energy and transforming it into electric.

b. Solar water pump Inverter

Control & adjust the system, convert DC into AC to drive the pump, adjust output power

in

real time through MPPT function.

c. Pump

The pump is driven by three-phase AC motor, drawing water from wells, rivers into water

tank or to irrigate directly. To meet the practical requirements and situation, the system

can work with different kinds of pumps, such as mixed flow pump, deep well pump, axial

pump, centrifugal pump.

3. Project

Refer to the true data of the system established in Hade desert of Xinjiang province, as

well as the successful operating experience from the project built in Takemala desert of

Xinjiang, a couple of figures attached for reference too.

1. Solar pumping station design and construction

To solve the irrigation problem of a shelter forest in desert, we designed a solar pumping

system in capacity of 15KW, PS15000.

Specifications for PS15000 as follows:

total power of station 15KW

Head 85m specifications for PV

array

Flow rate 36m3/h open-circuit voltage DC 685V

working voltage DC 556V short-circuit current DC 28.8A

Start light intensity 410W/m2 operating voltage DC 556V

End light intensity 360W/m2 operating current DC 26.4A

Pumping time( per day) 6~7.5h floor area 200m2

Quantity of water

pumping (per day)

135 m2 Watering area 70 acre(46,200m2)

The system was established in 2001, static level of the well: 24m, dune height:45m,

water salinity: 28mg/L

Effects in 2003

Oasis in 2010

2. Planting effects

Based on the actual natural environment along the road in Tali Mu desert, plants

selecting should ask for more attention on the characteristics of salt tolerance, drought

resistance, cold resistance, high temperature resistance, wind erosion and sand burial.

According to research findings and successful experience, Calligonum, Tamarisk and

Haloxylon should be the best choice.

3. Irrigation compare

(1) Flood irrigation. Working on the range of 400 m3/acre，not good for desert.

(2) Trickle irrigation. Working on the range of 120m3/acre

(3) Infiltrating irrigation. Working on the range of 80m3/acre, 5-7days irrigation cycle,

small evaporation, get away from damage cased by human and mouse, 1/3 water saved

and 3 times longer for use compared with trickle irrigation

Economical benefits analysis

According to the statistical data in early operation period of four years, if the equipment

depreciation is scheduled to 20 years, watering desert forest costs about $7.8/acre and

$0.06/ square meters annually.

Meanwhile, as people know, desert plant roots always have symbiont which has a great

medicinal value, such as Cistanche. Combining sand-break creation and cultivation of

medicinal herbs will produce good economic benefits, and also be pretty good for

sustainability of a shelter forest

Conclusions

The solar water pumping system has been running in good condition over the years

with high stability and reliability, without any fault. Solar plants irrigation is very

successful, and has great popularization and application value, can completely replace

the traditional fuel pump and reduce maintenance cost, zero pollution to environment.

Shenzhen Solartech Renewable Energy Co.,Ltd

Web: http://www.solartech.net.cn/ http://en.solartech.net.cn/

Tel: 86-0755-8615 1888