Solar Hybrid UPS
This type of UPS is both cost-effective and easy to install.
It is also one of the ways in which a company can go about adopting green technologies.
By Manjari Juneja
view of the huge demand supply gap in the Indian power sector, large scale use
of solar energy is imperative, especially given the abundant sunshine available
all over the country throughout the year. There is an opportunity, which is
being created due to the gross failure of the Indian power generation system.
That opportunity is what a lot of power equipment manufacturers are banking
After the National Solar mission was launched last year under the National Action
Plan on Climate change, wherein the target is to achieve about 20 gigawatts
of solar power by 2022, the concept of a solar hybrid UPS has taken off. A solar
hybrid system is basically a battery-based UPS, which apart from taking in AC
power, can also take power from solar panels, DC power, and finally output AC.
Solar hybrid technology is a green technology that enterprises can employ. Most
IT companies have a green mandate from their corporate body to source at least
some percentage of their energy through green means.
Ganesh Ramamoorthy, Principal Research Analyst, Gartner, said, Solar hybrid
technology involves the supplementary combination of AC as well as DC. It has
a direct implication for UPS applications. The power output from any solar system
is DC, so it makes sense to have a supplementary solar module which gives you
DC and then that DC can be converted into AC using the same equipment. The idea
is to bring in solar technology with the current UPS that you have and then
providing the supplementary/ auxiliary power unit that you want.
In the context of solar hybrid UPS, the government is offering Rs. 19 per watt
in the form of subsidy. It is also giving soft loans for the balance amount.
A person who goes for a 1,000 watt (1KW) solar hybrid UPS along with a battery
will get Rs. 19 per watt as subsidy. Also, on the remaining amount, he will
get a soft loan with a reduced interest rate, which is around 4-5%. It is making
customers look at it as a superior alternative.
How it works
Solar UPS have chargers that make appropriate use of solar panels. These can
be used for all types of loads and can be availed at nominal prices.
A Solar UPS is designed keeping in view the specific requirements of generating
AC mains power from the solar photovoltaic panels arranged in series and parallel
combinations to get the desired output at the desired current capacity. The
UPS is not directly connected to the panels. The panel modules, so arranged,
charge the batteries during the daytime and the UPS will derive the power for
inversion from batteries charged in this manner. The unit is designed to operate
as a standalone source of power and in no way does the mains utility from the
electric company come into the picture. The UPS has no changeover scheme as
it is on whenever needed, irrespective of the time of the day.
The unit basically consists of two partsa charge controller and inverter.
The charge controller is required primarily to prevent overcharging of batteries.
An additional LVD circuit is incorporated when a moderate DC load is to be controlled.
In a Solar UPS, it is used to prevent overcharging of batteries, reverse connection
of battery and reverse flow of current during the night. LVD action is carried
out in the inverter circuitry. Batteries are always operated in their safe window
of permissible high and low limits of terminal voltage.
An inverter is required to convert the DC voltage of a battery
to the required AC power. The net power output of these solar hybrid systems
is 5-10 KV.
|These can be categorized into three varieties:
||It is used to charge the battery and give the power
to 24V or 48V telecom equipment. The output is DC
||Where the input power is either solar or normal AC,
which feeds the battery as well as the load. When the AC input power is
unavailable and the battery starts discharging, solar input power comes
to the rescue
|Grid connected inverter
||The government is subsidizing solar power-based products
and it is offering approximately Rs. 19 per unit of solar power generated
through this technology
market for Solar Hybrid UPS is in bits and pockets. For SMBs or very small
industrial units, power supply is a huge concern and the usage of UPS
is high. Solar hybrid UPS is relevant for these markets in India"
- Ganesh Ramamoorthy,
Principal Research Analyst, Gartner
the central government came out with a policy and introduced incentives,
the solar hybrid UPS market has picked up. The government has subsidized
this product and it is also giving lots of incentives"
- Venkat Rao,
Country Manager, Medium and Large
UPS systems, Emerson Network Power
Global demand for solar energy is expected to grow over 80%
in 2010 and, in India, it is likely to grow fivefold to 150 MW. In the longer
term, the Indian market is poised to become a world-scale market by 2022, stimulated
by the supportive policies announced by the Government of India.
The solar power market is growing at a healthy trend of about 20% in India.
The overall power industry is pegged at $500 million of which 10 MW is the capacity
expected to be generated by solar hybrid systems.
Venkat Rao, Country Manager, Medium and Large UPS, Emerson Network Power, said,
After the central government came out with a policy and introduced incentives,
the solar hybrid UPS market has picked up. Earlier, it was dormant and only
a few organizations or the government used to go for it, owing to the cost.
However, now, the government has subsidized this product and it is also giving
lots of incentives, which is why people are looking at it quite seriously.
According to Gartner, the market for Solar Hybrid UPS is
in bits and pockets. It is in demand in areas where load shedding is frequent
and power outages are common. For SMBs or very small industrial units, power
supply is a huge concern and the usage of UPS is high. Solar hybrid UPS is relevant
for these markets in India.
Region-specific growth would vary in India. On an average,
across India, the growth would be between 30-35% depending on the state.
Where the power problem is acute, the growth rate in those
regions could be higher than this average.
Benefits of this technology
As the source of energy is light and the panel life is approximately 20 years,
it is a win-win situation to go in for solar hybrid UPS. The OPEX is literally
zero when it comes to these devices although the initial investment is high.
Nevertheless, you can reap the benefits for the next 20 years.
Conventional systems are dependent on AC input power and the cost amounts to
the total electricity consumed from the pole for which you have to pay. In hybrid
systems, during the day, the system relies on solar energy and it does not consume
AC power, which makes it a zero cost system except for the initial investment,
which is why people are going in for this technology.
Applications such as rural electrification, rural banking, rural industries,
offload platform requirement, domestic requirements etc. are driving the growth
of this category.
Challenges for this market include a high cost of generation. CAPEX is usually
two to three times that of conventional methods.
The other major cost is with regard to the acquisition of photovoltaic panels.
Reduction in the cost of these panels will be key to the overall adoption of
solar power-based products.
Efficiency of the panels is another issue. Till now the efficiency of the panel
ranges from 12-18%. This must go up and it may take time as this technology
is still evolving.
Also, the area required for these panels is too huge. You can't keep solar
panels just anywhere. It should be south facing and a number of other considerations
need to be kept in mind. To generate one MW of solar energy, the power panels
require five acres of land, added Rao.
For manufacturers, the biggest challenge would be to see how much energy is
going to be generated from a unit and how to push these units in the consumer
segment. They will also have to figure out how to enhance battery capacity.
Future of coexistence
Solar UPS technology will not replace existing UPS. Rather, it will coexist
with conventional systems as the total need for these cannot be fulfilled by
solar hybrid systems. The key to mass adoption is going to be cost reduction,
which will not happen without achieving large-scale supply.
Recently, the nuclear liability bill was also passed. This means that, after
some years, we will see nuclear power coming into the picture. With nuclear
power stations installed in India, it will fill in the power demand and supply
gap. As and when the power generation system in India gets better, the market
for UPS will diminish.