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The energy crisis is erroneously seen by many as a supply crisis. In fact, it is a wastage problem. An energy flow diagram I compiled in 2014 showed Pakistan was wasting 83 per cent of the primary energy (crude oil, natural gas, etc) by the time it converted to useful services like light, cooling, cooking, transport, etc.
The biggest wastage is of natural gas. This is tragic considering the immense gas loadshedding across Pakistan amidst expensive liquefied natural gas (LNG) imports.
Someone paying a monthly bill of Rs250 will not pay Rs1,000 to fix a gas leakage that reduces his bill to Rs125
The largest wastage of gas comes from the domestic and power sectors.
Domestic sector
The domestic sector consumed 6.8 million tonnes of oil equivalent (MTOE) of natural gas in 2016-17 compared to 3.9MTOE of electricity. Gas was used mainly for hot water for showers and a small amount for cooking. My eight-person household uses 18m3 per month on cooking three full meals daily. Compare that to electricity, which ran fans, lights, refrigerators, freezers, air conditioners, water pumps, TVs, computers, etc.
Gas leakages on consumer/demand side
There are no current estimates of the ratio of gas leakages on the consumer side. My home had 38pc leakage, my driver’s 70pc and my engineer’s 50pc. Several of my relatives had no leakage. So the average leakage per household may be in the range of 15-30pc on the consumer side.
Assuming the average leakage across all sectors is 15pc, like the leakage on the supply side, that comes to 209 million British thermal units (MMBTU) wasted, costing $2.25 billion yearly in LNG imports.
Although natural gas is cleaner than coal and petrol, the global warming potential of methane released into the atmosphere is 84 times that of carbon dioxide over a 20-year horizon. Any leakage on the supply and consumer side is drastically increasing our impact on global warming. Experts recommend that leakage should be less than 1.4pc to balance local pollution relief with the global warming impact.
Leakage and efficiency improvements are usually consumer-owned decisions to reduce utility bills. However, Rs121 per MMBTU in the lowest slab is too cheap to encourage efficiency. We are teaching the masses that gas is a cheap resource to be wasted.
Someone paying a Rs250 monthly gas bill will not pay Rs1,000 to fix a gas leakage that reduces his bill to Rs125. To that domestic consumer, the leakage costs only Rs125 a month. But that is a leakage of 0.9MMBTU, which Pakistan pays Rs1,500 a month to import as LNG.
The government has several options to reduce this leakage.
The lowest slab rates must be at least doubled to encourage consumers to identify and close leakages. This tariff increase is needed to teach our citizens that gas is not a cheap commodity.
SNGPL/SSGC should perform annual gas leakage checks for all domestic consumers (currently, consumers have to report a leakage). The government can pay SSGC and SNGPL for checking and fixing leakages. This method, although effective in the short-term, will incur recurring costs endlessly since the mindset of the masses will be unchanged.
In either scenario, a massive gas conservation awareness campaign should be launched to educate the masses as well as richer domestic consumers and industry/commercial sectors about gas leakages.
Leakages/UFG on supply side
In 2016-17, Pakistan produced and imported 34.6MTOE of natural gas. Only 29.3MTOE was delivered to consumers. If the current unaccounted-for gas (UFG) and leakage on the supply side of 5.35MTOE (roughly 15.4pc loss) is reduced to 1.4pc, then we can save $2.5bn in LNG imports yearly.
Geyser efficiencies
Boiler efficiencies exceed 80pc globally. However, geyser efficiencies in Pakistan are in the range of 25-30pc.
Hot water is heated not so much from the flame in the geyser, but mainly from the burnt gases when they are exhausted out through the hot water tank. Our conventional geysers are single-pass boilers. That means exhaust gases are vented in a straight line through the hot water storage tank from the burner. High-efficiency boilers (80pc efficiency) have multiple passes through the storage tank, zigzagging their way through the hot water storage, transferring more heat before they exit the geyser.
In addition, the already inefficient single-pass geysers are also switched on 24/7. There are heat losses from the storage tank throughout the day and the burner comes on frequently to heat the water even when no one is home. This results in higher consumption of gas or lower efficiencies.
SNGPL has made some improvements by introducing conical baffles (to slow down exhaust gases) and the Jal Bujh programmable timer device for geysers. They offer savings of 25pc each and can be fitted on to existing geysers. However, these measures lack publicity. They are not available through SSGC.
The government should immediately adopt these two measures and launch a nationwide campaign to spread their use to reduce gas consumption by half for domestic and commercial consumers.
Instant gas heaters entering the Pakistani market have multiple passes and heat water only when required, thus promising 70-80pc efficiency. They do have some challenges. The small diameter of their outlet pipe may cause a loss of water pressure in homes with larger pipe sizes. Also, a household may need several instant heaters as there is no storage tank to support simultaneous showers. That means new gas connections for bathrooms and kitchen, leading to higher plumbing costs. Hence, these are good options for new housing.
Larger-sized instant heaters (16-25 litres) made with multiple outlet pipe sizes would be ideal for most homes.
Hybrid instant gas heaters with small storage tanks are sold by companies like Ricoh Japan and provide an almost limitless supply of instant hot water due to high efficiencies. However, these are not available in Pakistan.
We don’t need to import heaters from abroad if our manufacturers produce multiple-pass, instant, highly efficient and correctly sized geysers.
Increasing geyser efficiencies from 25pc to 80pc would save $1.9bn in LNG imports yearly.
Power sector
Natural gas can produce power in simple cycle (gas turbine only) with efficiencies crossing 40pc. In combined cycle (steam turbine added to use waste heat from gas turbine), efficiencies can cross 60pc. In combined heat and power (like in our most efficient factories), efficiencies can cross 80pc.
However, some public power plants (Gencos) have efficiencies below 20pc. Our worst-performing power plants use 18,600BTU to produce 1kWh. The latest combined-cycle power projects in Pakistan have 62pc efficiency, using 5,500BTU/kWh of electricity. That’s why public power plants sell electricity at a price double what private power plants (IPPs) charge.
If our Gencos match the average performance of IPPs, it would double the electricity produced by them, or halve the gas used. If all gas power plants in Pakistan, whether private or public, match the performance of the highest efficiency combined-cycle plants in Pakistan (62pc), then gas consumption of power sector will fall from 452m MMBTU to 239m MMBTU, saving Pakistan $2.3bn yearly in LNG imports. Alternately, the current electricity generation of 41,426GWh will nearly double to 78,300GWh using the same amount of gas.
Industry
The industry consumed 7.99MTOE of natural gas last year. It can reduce gas consumption by installing high-efficiency combined heat and power (CHP) plants. Some factories in Pakistan are achieving efficiencies in their energy supply of between 70-80pc. If most factories adopt CHP and improve efficiencies to 80pc, savings would be substantial.
Massive savings are possible on the demand side when the electricity and heat (steam) produced by natural gas is used to run machines, motors, compressors, lights, cooling and industrial processes. Industrial energy demand can be drastically reduced by (a) eliminating compressed air and steam leakages, (b) adopting efficient machinery, motors and appliances and (c) better load management of processes, machines and motors.
Pakistan does not collect data on local industrial efficiency. But assuming the global average of 30pc (Global Energy Assessment), we have tremendous room for improvement. Most likely, our efficiency is lower than global averages. If we double industrial efficiency through improving supply-side and demand-side efficiencies, industrial consumption of natural gas will fall by 181m MMBTU, saving $1.95bn in LNG imports annually.
The industry could be encouraged to improve efficiency by giving preferential rates to those achieving CHP efficiencies above 70pc or those showing minimum 5pc demand-side efficiency improvements every year.
These savings are far greater than current LNG imports. They are 71pc of the current annual natural gas consumption of about 1.4bn MMBTU (29.3MTOE).
For too long we have focused on energy supply. However, energy efficiency is what will give us true energy security.
— The writer is an aerospace engineer and energy efficiency consultant
nida.farid@nrf-engineering.com
Published in Dawn, The Business and Finance Weekly, January 7th, 2019
