Reduce your electricity bills by using a high efficiency UPS systems

Did you know that difference of only 1 % in efficiency in Online UPS system can save more than 3 lakhs rupees per year?

An Online UPS is ON 24 hours of the day 365 days in a year, except in the case of a voluntary shutdown. It consumes electricity all the time.

So if you are using an online UPS system at your office you should seriously consider how much efficient your UPS is and how much you tend to lose out.

When making a buying decision for a UPS , companies generally look at intial cost of the system. But the Total cost of ownership is more often not calculated and ignored. Now a days there is increasing emphasis on reducing the costs in business process. Energy costs should also be taken into account.

TCO( total cost of Ownership) = Initial cost of UPS + Maintenance charges + Running charges.

The amount wasted due to inefficiency in 1-2 years can be equal to the cost of the UPS itself.!!!!!!

What is UPS efficiency?
Energy efficiency of a UPS can be expressed as the difference between the amount of energy that goes into a UPS vs. the amount of useful energy the comes out of the UPS to power your loads. In all UPS systems, some amount of energy is lost as heat when it passes through the internal components of the UPS (transformers, rectifiers, inverters etc.).
The less efficient the UPS is, the more heat it will reject. This means air conditioning energy costs are also lower by using a high efficiency UPS. It takes an extra 3,400 BTU per kW of heat lost by the UPS to maintain the room temperature. A typical air conditioner requires 0.3 kW of energy to generate 3,400 BTU of cooling. As a rule, the air conditioning costs equal 33 per cent of the of the kW costs of lost energy of the UPS. So air conditioning charges would increases as the heat dissipated by UPS increases.

So the equation above becomes
TCO( total cost of Ownership) = Initial cost of UPS + Maintenance charges + electricity consumption by UPS+ Air conditioning charges.
Cost savings from using a high efficiency UPS often equals the value of the UPS in as little as 3 to 5 years.

Just how much energy is lost between the input and output can be significant when you consider how much the wasted energy is costing. Energy efficiency advantages of as little as 1 percent between one UPS and another can translate into thousands to lakhs of rupees saved per year depending on the size of the UPS.

Let us take an example of 100kW UPS

90% efficiency would mean loss 10kW.

10 kW of lost energy may not seem like a lot of power, however, UPS loads operate continuously 365 days a year.

10 kW of used energy now equates to 87600 kWh of power wasted each year.( 24hours x 365days x 10 kWh)

1kWH equals to one unit of electricity.

With a meter rate of Rs. 6/unit, this equates to Rs. 5,25,600 of energy wasted by the UPS and an additional Rs 1,73,448 in extra energy costs just to cool the heat ejected by the UPS — resulting in a total of Rs. 6,99,048 in electricity wasted !

No matter what UPS system you select, there will be some energy lost between the utility and the output, but high efficiency UPS systems can dramatically limit the energy loss, resulting in substantial cost savings.

Consider the previous scenario.

What if the same UPS was 95% efficient as opposed to 90 % efficient losing only 5 kW of energy as heat. The difference in energy savings would be over Rs. 3,49,524 per year!!!!!!

How do you know if you are getting a high efficiency UPS?
When comparing the energy efficiency of UPS vendors, published efficiency specifications from UPS vendors may all seem very similar, leaving you to wonder whether there is any difference between manufacturers. The only way to ensure that a UPS vendor is giving you straight facts about efficiency is to demand a witness test on your specific UPS prior to shipment from the factory. As a customer you have the right to know.

An efficiency test is like test-driving a car to measure fuel efficiency. Just as cars get radically different mileage when driving on the highway vs. a windy mountain road, UPS efficiency also can change with the type of load it powers. Today almost all UPS power 100 per cent non-linear loads (computers, servers, motors and electronic equipment).

When most manufacturers test their UPS, they use linear loads, which are not representative of customers’ actual loads. This is very convenient for some manufacturers, as UPS efficiency will often be much higher when powering linear loads. Some manufacturers won’t show the customer the true energy consumption of the UPS when installed at their site. Only by insisting that manufacturers demonstrate efficiency with non-linear loads representative of real world environments can you be sure of the UPS true efficiency.

The second major factor to influence UPS efficiency is at what power level the efficiency is measured. Just like a car will have its best mileage operating at around 60 mph, most UPS typically will have their best efficiency operating at 50 per cent to 100 per cent load level. Again in the real world, most UPS systems operate at 25 per cent to 60 per cent of their nominal load — not fully loaded.

To determine accurate efficiency, the UPS should demonstrate efficiency at loads below 25-50 per cent where most UPSs will likely be operating, especially if operating in redundant configurations. Hardly any UPS systems run at 100% load and those that are in N+1 or 2(N+1) redundant configurations rarely exceed 30% load per module.

Only by testing your UPS under actual expected load levels (25-50 per cent in most cases).and simulating an actual load profile in your facility will you know the real efficiency of your UPS.

How much will a high efficiency UPS save you?

To calculate how much you will save using a high efficiency UPS, estimate your actual load and utility rate category. Calculate efficiency based on example given above

Some things to think about when buying a UPS system

Below are some general questions when buying  a UPS system:

Off-line

An off-line unit would be the most basic UPS system as the load is supplied by raw mains until such times that the voltage or frequency would go outside the preset tolerance levels at which time the system would support the load via its battery. These units are primarily used for PC’s or servers but should not be used in an area were the local power supply is particularly unstable.

True online double conversion

True online double conversion UPS systems, due to the continual AC to DC followed by DC to AC conversion, provide a consistent quality of power. As the UPS output is independent of the mains input no matter what disturbances or fluctuations there may be on the mains supply there will always be a clean controlled output. This type of system is suitable for all applications were a high availability of supply is required.

Redundancy

Redundant systems are utilized in order to provide added resilience to further reduce the risk of a power failure. Multiple UPS systems are connected together sharing the load, this enables essential maintenance and repairs to be carried out on any of the connected modules without having to transfer the load to mains supply.

Scalability

Scalability is for instances when it is estimated that the load may increase in the future so the UPS system should be scaled up to match the demand. It is also used where the budget for the UPS requires that a smaller system can be purchased at the outset to suit the current load with additional modules

Communications

UPS systems have various options for communications such as volt free contacts for connection to the buildings BMS to network connectability enabling SNMP. It is best to decide on communication options from the outset so that the necessary cabling etc can be installed.

Contact Us

If you need any more information, or if we can help you in any way, then please contact us by sending us an email on sales@microsystemservices.com