What are Solar Home Systems?
What are Solar Home Systems?
Imagine you live in a house that has no access to the energy grid. It is challenging to follow any activities after the sun has set without light, you cannot charge your phone or use any device that requires electricity. The national government might have promised to enlarge the energy grid; however, this will take several years. What can be done to solve this dilemma? How can you gain access to some of the most basic functions billions of people have already access to? Solar Home Systems can be a solution.
The solution is to foster one’s own off-grid energy. But how to do that? Solar home systems offer an excellent option for off-grid energy supply. Especially in rural areas of low-income countries solar home systems (SHS) are gaining more and more popularity within the population. Bangladesh has been a pioneer of the solar home system movement and had tremendous success in rural electrification.
What are Solar Home Systems?
This is how they work: Solar Home Systems basically consist of solar panels which are built on the roof of one’s house. The energy gained through the solar panels then directly feeds into the electric circuit of the house. Typically, one SHS can power between three to eight devices for up to five hours per day, for instance one LED lamp, one smart phone charger and one rice cooker. The amount of energy depends on the capacity of the solar panel(s). A SHS can cost between 300 and 1000€ depending on its size, quality and the country it is sold in (Bright Green Energy Foundation, 2016 (worldfuturecouncil.org)).
Learning from Bangladesh
In Bangladesh, SHS are already supplying over 25 million people with energy, and more than 4 million SHS have been installed since the beginning of the century (Jones and Warren, 2020). As one of the most populous countries in the world with a rapidly growing population, cramped in a comparatively small-sized country, Bangladesh has been facing increased energy poverty and lack of economic opportunities. The exceptional growth in SHS has mitigated some of these effects the country has been facing since the end of the 20th century. The energy generation of the country could not keep up with its demand. Especially rural areas were affected, because an extension of the energy grid would have been to cost-intensive for the government at the time. To satisfy most of the energy demand has led to an increase in imports, which were often cheaper than extending the grid. Therefore, considering an extension of the energy grid was not seriously considered in the past. SHSs became interesting because an extension of the energy grid could be avoided while providing the rural population with stable energy access (What Tanzania can learn from Bangladesh on energy access (worldfuturecouncil.org).
A central government agency was set into place that distributed funding – in the form of microcredits – to smaller local NGOs and enterprises, which in turn organized the installation and maintaining of the SHSs.
What made the SHSs especially successful also within the rural population was the pricing model. Normally, a SHS would cost maybe around 1000€ – a price hardly affordable by most of Bangladesh’s population – , however the local NGOs and enterprises offered an instalment-model: A down-payment of 25% to 50% had to be made, the remaining amount could be paid in monthly instalments (Bright Green Energy Foundation, 2016 (worldfuturecouncil.org). Over the years SHS became more and more popular, leading to their current success in Bangladesh and contributing to the energy access of many parts of the country’s rural population. After having paid off the instalments, the SHS is owned completely and usually supplies energy for the next 20 years, virtually without ongoing costs except maintenance. That means the owner of the SHS is independent of the national energy grid.
Why are Solar Home Systems important?
The access to energy provided by the SHS had many advantages for the rural population: It enabled local businesses to have longer opening hours which could therefore make more profit. Children were able to study longer in the evening and improve their access to education. LED lamps could be installed, therefore making the health detriment kerosine lamps become obsolete and jobs were created aplenty (What Tanzania can learn from Bangladesh on energy access (worldfuturecouncil.org)).
SHS also impact the general social infrastructures of a region. This is most evident in the creation of green jobs. The SHS have to be installed and maintained by someone, thus creating jobs at the local level within the area of renewable energy. Moreover, SHS contribute to the empowerment of both youth and women. Women are able to work in a wider range of professions both from home and within the sector of renewable energy. Generally speaking, energy is essential to development (Lessons learned from the development of 100% RE roadmaps (worldfuturecouncil.org)).
The development of SHSs should be actively pursued. In order for it to consistently grow, rural populations need financial assistance, for instance in form of micro-credits, as well as affordable prices and fair conditions for the purchase of a SHS. Workforce for installation and maintenance needs to be trained, in the best case the workforce comes from the respective communities using SHSs. Moreover, the benefits of SHSs need to be promoted to a wider population and actors across different sectors.
If you want to know more, here are some articles that might interest you:
What Tanzania can learn from Bangladesh on energy access (worldfuturecouncil.org)
Seizing the Solar Energy Revolution in Tanzania (worldfuturecouncil.org)
Bright Green Energy Foundation, 2016 (worldfuturecouncil.org)
Lessons learned from the development of 100% RE roadmaps (worldfuturecouncil.org)
- Brief introduction of solar home system
Solar home system: SHS (Solar Home System). Mainly refers to the small photovoltaic power generation system installed in office buildings and residential buildings to supply power to the residents themselves. During the day, the power generation system charges the battery; in the evening, the power generation system discharges the electric energy stored in the battery to realize power supply to household loads.
Its composition is as follows:
- PV modules
Solar panels are the core part of the solar power generation system and the most valuable part of the solar power generation system. Its role is to convert solar energy into electric energy or sent it to the storage battery or drive the load. The quality and cost of solar panels will directly determine the quality and cost of the entire system.
The raw material of solar panel includes cells, glass, EVA, TPT, and aluminum alloy frame.
- Controller
The solar controller is composed of a dedicated processor CPU, electronic components, displays, and switching power tubes.
- Battery
Generally, lead-acid batteries, generally 12V and 24V two kinds, in small and microsystems, Lithium Iron Phosphate batteries, nickel-cadmium batteries, or lithium batteries can also be used. Its function is to store the electrical energy generated by the solar panel when there is light, and then release it when needed.
- Inverter
In many cases, AC power is required.
There are two kinds of electricity, DC and AC. Homes that are connected to utility power use AC electricity. Flashlights, small radios, and automobiles use DC electricity. The direct output of the solar generation system is generally direct current, which needs to convert the DC (direct current) generated by the solar power system into AC (alternating current), so an inverter is required. An inverter is a device that converts direct current (DC) into alternating current (AC).
- Classification of Solar Home System
Household solar power generation is divided into off-grid power generation system and grid-connected power generation system:
- Off-grid solar home systems.
It is mainly composed of solar cell components, controllers, and storage batteries. To supply power to AC loads, an AC inverter is also required.
( YelloBox—4 rooms lighting and 2 ports for phone charging )
( Mbox — Power home lighting, phone charging, fan, TV, radio, solar torch )
- Grid-connected solar home system.
It means that the direct current generated by solar modules is converted into alternating current that meets the requirements of the commercial power grid by a grid-connected inverter and then directly connected to the public grid.
Grid-connected power generation systems include centralized large-scale grid-connected power stations, which are generally national-level power stations. The main feature is that the generated energy is directly transmitted to the grid, and the grid is uniformly deployed to supply power to users. However, this kind of power station has a large investment, a long construction period, and a large area, and its development is relatively difficult. The distributed small-scale grid-connected power generation system, especially the photovoltaic building integrated power generation system, is the mainstream of grid-connected power generation due to the advantages of small investment, fast construction, small footprint, and large policy support.
- Advantages of solar home system
- Solar energy is inexhaustible.
The solar radiation energy received on the earth’s surface can meet 10,000 times the global energy demand. As long as solar PV systems are installed on 4% of the world’s deserts, the electricity generated can meet global needs. Solar power generation is safe and reliable, and will not suffer the impact of the energy crisis or unstable fuel market.
(2) Solar energy can be everywhere, and power can be supplied nearby without long-distance transmission, which avoids the loss of long-distance power transmission lines;
(3) Solar energy does not use fuel, and the operating cost is very low;
(4) Solar home system has no moving parts, is not easy to damage, and is simple to maintain. It is especially suitable for unattended use;
(5) Solar home system does not produce any waste, has no pollution, noise, and other public hazards, and has no adverse effects on the environment. It is ideal clean energy;
(6) The solar home system has a short construction period, is convenient and flexible, and can add or reduce the amount of solar power capacity according to the demand of the household to avoid waste.
- Application fields
- Small power supplies ranging from 10 to 100W are used for military and civilian life in remote areas without electricity, such as plateaus, islands, pastoral areas, border posts, etc., such as lighting, TV, radio, etc.;
( Apollo—Room lighting, radio, phone charging, fan, TV)
- 3-5KW home roof grid-connected Solar Power Generation System;
- Solar water pump: to solve the drinking and irrigation of deepwater wells in areas without electricity;
(4) Solar water purifier: to solve the problem of drinking water and purified water quality in areas without electricity.
Shenzhen Solar Run Energy
Solar Run enables people to replace deleterious and expensive kerosene lanterns and candles with modern solar energy that can power lights, cellphones, TVs, fans, and other small electronic devices. To make off-grid people’s life easier and more comfortable.
Solar Run hopes to bring more happiness to people in power-intensive areas with our high-quality products in the future.