fangpusun company sets up the whole process of 3.5kw off-grid pv system

off-grid pv system is mainly used in off-grid access or energy storage system, such as isolated mountainous areas and isolated islands. off-grid pv system is mainly composed of pv modules, solar charge controller, solar off-grid inverter, battery pack, some solar inverter can also be connected to a generator.

in a off grid hybrid solar system like the one shown above, the pv module converts solar energy into electricity, which is then stored in a battery via a solar charge controller. the solar inverter powers the load. some solar inverters can also connect a generator and set the parameters to automatically start the generator when needed.

first, the load situation

considering the usage scenarios of main household electricity, the general household appliances are as follows:

lighting：200w

refrigerator：50w*24  inductive load  starting power:250w

air conditioning：750w  inductive load  starting power:2400w

tv：50w*6    

desktop*3：600w  

microwave oven：700w  inductive load  starting power:1200w

washing machine：300w

electric fan：50w  inductive load  starting power:150w

total：3000w

second,electricity consumption

lighting：200w*6h=1.2kw•h

refrigerator：50w*24h=1.2kw•h

air conditioning：750w*4h=3kw•h

tv：50w*6h=0.3kw•h   

desktop*3：600w*2=1.2kw•h  

microwave oven：700w*0.5=0.35kw•h

washing machine：300w*1=0.3kw•h

electric fan：50w*8=0.4kw•h

total：about  7-10kw•h

third, solar pv system components

1. the inverter

the main function of the inverter is to convert direct current into alternating current and supply energy for the alternating current load.

       in terms of demand, the power of the load is about 3000w, plus some inductive loads, which have large starting power, you can choose xtalent series xtm/psh4000-48. the inverter of this model can continuously output 3500w, and can withstand a load of 4000w within half an hour, or up to 10500w within 5s. it's a good choice.

2. the battery

according to the data, it consumes about 7-10 kwh of electricity every day, so we need to choose 4 12v and 200ah batteries in series, which can theoretically store 9.6 kwh of electricity.

considering the load conditions, use environment, service life and cost factors, there are cost constraints where the general choice of colloidal lead-acid maintenance-free battery or lithium battery. users should not choose inferior batteries for the sake of cheap, because this will affect the reliability of the entire system and may cause greater losses.

3. pv modules

pv modules convert solar energy into direct current electricity

if the normal light is 4.5 hours and the off-grid pv system has a power loss rate of 0.2, it needs an average of 10 kwh of electricity per day and at least 27,777w of solar panels.

4. solar charge controller

the role of the solar controller is to generate electricity from the photovoltaic module, store it in the battery and protect the battery.

5. the generator

fangpusun xtalent series inverters can be connected in parallel with generators in the off-grid solar systems and off grid hybrid solar system, and the start-up time of generators can be programmed to create a flexible and stable off-grid photovoltaic system