How Reciprocating Engine Generators Stack up Against Battery Storage Systems

Here’s how both energy options compare with regards to cost, flexibility, and environmental effects.

Alternative energy providers all across Canada sure enjoy debating why their product or solution reigns supreme over all the rest. With so many different product offerings in the energy space today, it’s no question that each will have their own set of advantages and disadvantages.

With that said, end users will typically place most value in a few key areas when considering alternate energy: affordability, flexibility, and the effects on the environment.

In this blog, we’ll compare two common solutions in the energy space: reciprocating engine generators and batteries/UPS.

When considering engine generators, flexibility wins:

One excellent quality that natural gas engine generators provide is flexibility. Engine generators are used as a backup power source for many different building and infrastructure types in the event of power outages. In fact, generators are required by code to maintain life safety systems in hospitals, high rises and military bases.

For larger energy consumers, one of the more intriguing benefits of engine generators is that they can be set up to run continuously (prime power) for well under 10 cents per KWH, including fuel and maintenance. To put this in perspective, the average cost for hydro in Ontario per kWh ranges between twelve and thirteen cents. Thus, savings can ultimately be plentiful when comparing against the utility grid.

Another great thing to keep in mind when considering generators: Generators provide more than just electricity - they also generate very useful heat. CHP (combined heat and power) provides a continuous supply of hot water or steam which can be used for industrial heating or cooling. And the cherry on top is that the CO2 that is produced by gensets can be captured to feed crops in agriculture or greenhouse settings.

When weighing the effects gensets have on the environment, it is important to understand that the effects are largely determined by the fuel source that is being burned.

Diesel is not a great option for any energy initiatives outside of standby applications as they are heavy polluters - and retrofitting with emission reduction systems is a financial blow. Natural gas, however, is a great choice to run generators if infrastructure is available.

Natural gas engines have significantly lower emissions compared to diesel, in addition to running quieter and costing significantly less. Natural gas engines do have emissions, and for a 1MW peak shaving setup that runs about 50 hours/year, that will equate to about half a kilo of CO2/kWh. Peak shaving systems are run when the hydro grid is at a high demand and in some locations, running a genset will actually be cleaner than the hydro grid supplying electricity!

When considering batteries, maintenance cost wins:

When we look at batteries, there are certainly instances where batteries are a better fit vs gensets.

For one, costs are always a key consideration in any energy project - and in most cases with battery projects, they have a significant price tag attached to them. Capital overhead (installed cost) of a BESS (Battery Energy Storage System) have dropped significantly over the last decade but still remain very expensive with an approximate value of $200/kWh for a lithium-ion battery system. However, what a battery system lacks in capex affordability, it makes up for in maintenance costs. In fact, maintenance costs are said to be in the neighbourhood of 2.5% of the $/kW capital costs - with a system that costs $1,300/ kW costing about $32.50 to maintain. In the case against gensets, batteries will win that battle in most cases.

Battery systems do not have the flexibility of gensets, but certainly play a very important role in certain applications.

One of those examples would be in microgrids, as batteries assist with storing and balancing energy that is produced by alternative sources (solar, wind, etc). Some regions of the province and country rely on batteries to regulate frequencies, for flexible ramping and aid in black starts. In the U.S and Europe, large-scale battery systems are being deployed for capacity reserves in commercial applications. That concept has not quite picked up traction here in Canada as of yet, but the day might be coming.

As we have seen over the last few years, there is an abundance of focus on the environment as we move forward with the world’s energy.

BESS systems are certainly viewed as a great solution as they do not omit any emissions when being utilized. However, much of the impact batteries have on the environment does not occur when they are being used, however does occur in the production stage. Lithium mining, cobalt mining and graphite mining - which are all key ingredients in energy storage solutions - are taking a toll on the environment in certain regions around the world. In fact, it is thought that battery production causes more environmental damage than carbon emissions alone, with water sources, food production and air quality all being areas that mining key battery components are affecting.

The bottom line is: No matter which way you look at it, we can find the pros and cons in both energy options.

Natural gas generators provide the flexibility that so many business owners and operators value with their energy demands, while batteries provide excellent reliability when working in conjunction with the utility grid.

Whether you need to vary your output levels, shift energy demands throughout the day, run your plant continuously or just need emergency back up power - our T&T Power Group has a solution for you.

Don’t hesitate to contact us today to learn more. We’re here to help!


Posted by Ben Tinklin | Feb 26, 2021 | Categories: Power Generation