The Top 5 Benefits of Gas Generators for Data Centers
Published 11 December 2020
There is no secret that data centers are one of the biggest consumers of electricity and water with a growing target of carbon neutral advocates.
Presently, data center operators are highly reliant on diesel generators to power their facilities due to the infrastructure availability and low fuel prices. However, this is becoming increasingly exorbitant and exceedingly unsustainable.
“If you ask a data center operator, the big end users will want to become carbon neutral by 2030. Whilst natural gas gensets are not carbon neutral, they are a step towards the right direction,” said C. B. Lim, the Director of Product Development and Management at AWI-Genz Global Private Limited.
The data center industry has been growing to accommodate hyperscale cloud firms, cultivate ecosystems and fulfill new demand arising from technologies such as AI and IoT. Many tech giants and data center providers are committed to renewable energy goals, turning to greener alternatives like natural gas generators for their data centers, as they offer a number of benefits.
“I predict that green hydrogen power will be the future fuel for data center power, but you cannot just stand straight there! Infrastructure needs to be available. Hence, we see the gas genset as an intermediary solution for the foreseeable future. Natural Gas distribution networks could be used for hydrogen distribution in the future with many countries already ensuring any new expansion or replacement of natural gas networks can be used for both gas and hydrogen types,” Mr. Lim posited.
1. Reduced Carbon Footprint
Data center operators recognise that being carbon neutral plays an important role in their sustainability and Corporate Social Responsibility (CSR) stratagem and at the same time, enabling them to do their bit for global climate change. They also perceive that individuals and corporate customers prefer to buy products and services from environmentally conscious suppliers.
With this, more eyes are on gas generators as a practically immediate solution to reduce carbon footprints. Even with 30% reduction in carbon emission after switching to gas generators, many data centers are still using diesel generators as the primary source of power. And the demand for power and electricity is expected to rise continuously in the long run. This shows that switching to a lower carbon solution is essential as the climate clock is running out of time until the climate conditions become detrimental and irreversible.
“In a typical data center, the diesel generator set is a de-energised system. It is on standby mode, sat there doing nothing!” said Mr. Lim.
Gas generators are not meant for a one time one-for-one replacement for diesel generators. It is a commitment for operators, owners and organisations to change their mindset in order to understand the full benefits of the system and utilise them for continual operation.
“Emissions savings up to 40% as compared to a diesel genset and for utility grids dependent on region could be up to 60%,” said Mr. Lim.
“If we look at Singapore, all the electricity is created from liquefied natural gas (LNG) power plants. If we put a gas power plant in a Singapore data center, we can localise the power generation,” added Mr. Lim.
In the conventional set up with diesel generators in Singapore, the utilities companies have to provide both power and transmission losses for customers. Transmission losses can go up to 15% of the usable power generated and this will result in a negative effect on a country’s overall carbon footprint.
“If you can reduce the transmission losses by producing locally, then it’s better for everyone,” advised Mr. Lim.
Towards a localised gas power generation for data centers, AWI-Genz Global recommends using a Combined Heat and Power (CHP) system.
Instead of dispersing the heat from exhaust, water jacket and oil into the atmosphere as pollutants, this integrated system takes the heat and inject it into an absorption chiller that normally uses lesser electricity as compared to a normal chiller, and convert the heat into the chilled water to keep the servers cool to prevent any damages to the servers which will result in downtime.
“You’re utilising the heat from the engine to cool the data center. It is going to save you a lot of money,” said Mr. Lim.
2. Reduced Power Utilisation Effectiveness
Data center operators are constantly seeking to reduce their power utilisation effectiveness (PUE) to the highly sought after 1.0 PUE ratio.
“For PUE, what we are looking at is to reduce the transmission losses of the data center, and the majority of the losses come from the cooling system and the electrical power train driving the IT and cooling systems,” said Mr. Lim.
By using the CHP gas gensets, data center operators can also significantly reduce their PUEs.
Another key component that affects the PUE ratios is the uninterruptible power supply (UPS). UPS is commonly used for power conditioning and bridging the gap between utility and diesel generators during utility failures. A typical efficiency range of a static UPS is approximately 92% – 96% without any energy storage losses.
Looking at the power requirements of modern IT equipment (ITIC CBEMA), a UPS is typically not required.
Maintenance and overhaul play a significant role in the operating cost for gas gensets. In order to effectively utilise your assets, running the genset at their upper limit continuously is required. These fundamentals are applicable for both gas genset and hydrogen fuel cells.
“The key driver for natural gas genset is that you’re buying an asset that is used 24/7, rather than just an asset that sits in its container and does nothing,” said Mr. Lim.
Therefore, with the reduction of components needed for a natural gas-powered data center, operators can reduce the cost of equipment and space required for the facilities.
At the same time the noise emission of gas genset is approximately 20% lower than conventional diesel genset.
Switching to gas gensets in countries such as Indonesia, Malaysia and Philippines will be very reasonable for Data Center as there will be a potential cost saving of up to 25% as compared to countries like Singapore.
“We see Malaysia, Thailand and Indonesia have been very good markets because of their great distribution networks for natural gas. As for the Philippines, apart from lack of gas distribution, the low gas prices in the Philippines will still make gas gensets very attractive.” added Mr. Lim.
But you may ask, ‘What about Singapore, one of the most matured data center markets in Southeast Asia?’
Mr. Lim believes that it may be difficult to operate a data center solely using gas genset in Singapore because there are limited natural gas pipelines available in Singapore. This means that the natural gas supply has to come in tube trailers form.
“If you are looking at a natural gas-powered data center, the amount of gas needed and the storage space for the gas supply to keep the generators running would be immense. It is not feasible for Singapore data center operators to utilise natural gas gensets” said Mr. Lim.
Therefore, it will take some time for Singapore to switch from diesel genset to natural gas genset.
3. Improved Electrical Infrastructure
“In order for the data centers to shift to a cleaner energy source such as natural gas or hydrogen, I think data certification boards will need to take a look at the topologies involved and the way they accredit data centers. New technologies for powertrain will drive new distribution topologies,” said Mr. Lim.
Take for example a 2.5MW gas genset in a distributed redundant basing on “¾ topology” powering up a data center. In normal operation, each of the four gas gensets will have a max loading of 75%. If a failure occurs on one of the gas gensets, the load will transfer to the others, each of the others potentially receiving a 25% load increase.
This will result in frequency drop on the gas genset because they do not handle step load as well as diesel genset. One way to get over this would be to utilise a frequency stabiliser instead of a static UPS. Or if you like, a hybrid UPS like ONE Power Solutions, which is offered by Power Partners.
“The beauty of this hybrid UPS is that we only need a frequency stabiliser of about 600 kilowatts because we’re only looking at this 25% load transferring, and energy storage required would, in theory, need to be just 10-15 seconds. This opens up the possibilities of ultracapacitors, which are a green solution as compared to lithium batteries. With their long life of 15 years, they require no recycling at the end-of-life cycle. In a traditional data center, the UPS for this unit would need to be 2.5 MW with a 10-minute lithium-ion battery,” said Mr. Lim.
“Distributed redundant, traditional 2N solution; these don’t really work with gas gensets or hydrogen fuel cells, because you really want to maximise the kWh. So, you do not want to have all that reserve power in the stationary engine just for failure transfer,” added Mr. Lim.
AWI-Genz Global’s Active Catcher Topology for gas-powered data centers could allow generators to run up to 95% load and still have reserve set to transfer to in the event of a failure. Mr. Lim predicts static switches will play an important role in new green data centers of the future.
With emerging new distribution topologies, data centers powered by gas gensets can feel assured that their facilities are going to be reliable. In a current data center, the prime source of power (the diesel genset) is de-energised until required.
“Let’s think of it like driving a car. If you keep the car running all the time, you don’t have to worry about the engine starting. As we all know 99% of diesel gensets’ failures are ‘Failure to start’. The reality with diesel gensets is when you need it the most, it is most likely to let you down”, commented by Mr. Lim.
“In a de-energised system, it is very difficult to predict a failure. But when something is continually operational, you can see small changes in the telemetry that can help predict issues before they occur, so you can be more proactive on your maintenance”, said Mr. Lim.
As a part of Air Water Group who specialise in gases and liquids, AWI-Genz Global has developed its own in-house LNG storage solutions to complement and expand the resilience of the overall gas genset. Therefore, when a problem occurs with the natural gas supply, the data center will continue to run on natural gas from mobile tube trailers.
“We want to have some storage on-site as well, so that’s one thing that is unique to i-Genz that we can put in as a part of the package”, said Mr. Lim.
5. Grid Systems Stabilisation
In countries like Vietnam and Indonesia where the national grid systems may be less reliable and less environmentally-friendly, the implementation of gas generators in data centers could help stabilise the systems.
“I think a data center itself will become a microgrid in the future where all these little microgrids can link together and help one another,” said Mr. Lim.
With the increased resilience brought by gas gensets, these engines could run in parallel with the utility to not only provide power to the data center, but also to surrounding local communities.
“When you have all these little power plants running in parallel, it means that the grid itself doesn’t have to have such a large spinning reserve,” said Mr. Lim.
And with more data centers building their own power supplies, we may see data centers with gas power that is fully off the grid, enabling them to be built almost anywhere.
“Maybe we’ll even see innovation parks coming up where the data center is really the powerhouse, and there may be some office buildings around that utilise power generated from the data center. There’s a whole separate community that could be created off the grid,” predicted by Mr. Lim.
Despite the potential cost saving and environmental benefits, there is still not much support for co-generation of power in many grid systems, and this may be a sticking point in Asia.
“That’s one thing that may need to change and will have to change when renewable energies become more popular in certain countries,” posited Mr. Lim.
The trend towards renewable energy and environmentally-friendly initiatives seems to be unstoppable at this point.
“There has to be a natural progression. The easy way to progress would be straight to hydrogen power and there are solutions that we have for hydrogen fuel cells that are built for data centers,” said Mr. Lim.
At the moment there are limited hydrogen pipelines in the world. Storing hydrogen can be used as an alternative solution. However, disasters like the Hindenburg Zeppelin, a German passenger airship that exploded in May 1937, in New Jersey, USA is bringing hydrogen into disrepute.
“People are not quite ready to accept hydrogen, and the infrastructure is not there yet. But we see there is going to be a progression from diesel to something that is less damaging to the environment, which would be natural gas”, predicted by Mr. Lim.
Nevertheless, with the benefit of safety, lower cost and low emission brought by gas generators, the prolific future of natural gas-powered data centers will be inevitable.
By Stuart Crowley, Editor