Can Rooftop Solar Power Replace All Diesel Consumption from Gensets? - India Renewable Energy Consulting – Solar, Biomass, Wind, Cleantech
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 This is a question we keep getting at EAI – is it possible to replace all our diesel consumption using rooftop solar power?

While we can get into a detailed analysis on the combination of conditions under which such a replacement is indeed possible, the brief answer to the question is: Typically, with the current state of technology for both solar inverters and diesel gensets, it will be difficult to replace beyond 50% of diesel consumption using rooftop solar power.

It might be possible in some cases based on factors such as the nature of the load, timing of load shedding, etc., but for many commercial/industrial units 100% replacement of diesel power with rooftop solar is unlikely.

Why is it so difficult to replace all diesel consumption from backup gensets with rooftop solar power? This blog post provides details.

Part of the content for this post was derived from Solar Mango – the Rooftop Solar resource.

The main reasons why, with the current technology and systems, solar power cannot completely replace (in most cases) diesel as a backup energy source are:

1. Load shedding often happens during night times; unless a company uses medium-large sized batteries to store solar energy produced during daytime (a very expensive proposition), the facility will have to depend on diesel for power generation during nights.

2. Load requirements might be much more than what the solar system that can be accommodated on the rooftop can supply. This is especially true for companies having only a small or medium sized rooftop but significant power loads.

3. Solar power is not firm – even in cases where enough rooftop space is available, the loads required are not large and load shedding happens during daytime, a facility might not be able to entirely depend on solar because solar power is not a firm source of power. There could be rainy/gloomy days when there is little/no power produced from the solar panels. Once again, in the absence of large-sized batteries that can provide many days of autonomy (almost too expensive a proposition under current tech maturity and energy storage costs), a firm backup power source such as diesel will be required.

But let us also look at cases in which solar power can indeed replace all or almost all the diesel usage from gensets. These would be possible even today for the following cases

1. This can happen where a parallel, off-grid solar power system can power the devices during power cuts. This applies when the total loads are low, light and non-critical (just lights and fans, for instance). Usually, this scenario is not frequent as industries rarely use diesel solely for such non critical loads alone.

2. For typical commercial or industrial enterprises where load requirements are much higher as well as gensets are used for heavy and critical loads, such a 100% or near 100% replacement is still possible where the rooftop availability is large (hence solar power can provide all the aggregate power required during power cuts),  an intelligent battery based system is used to tide over the infirmness of solar power and where the load shedding/power cuts happen mainly during sunshine hours.

So, in summary, for most of us while the day is not yet there when solar power can completely replace diesel consumption, such a day might not be far away and we are already at a stage when it is worth making a start.

To provide you with some a key takeaway, a recent study by EAI inferred that for most small and medium manufacturing units in Chennai for instance, the likely % of diesel replacement with solar power use will be about 35%. Of course, this is just an average number and differs from one unit to another, but it provides an indicative estimate of what is feasible today.

EAI’s Diesel to Solar Report – The one and only such report in the world

EAI has published a unique report to assist those keen on using solar power to offset their diesel consumption.

What are the best diesel reductions possible using rooftop solar? Under what conditions and with what strategies can companies maximise the benefits from solar power and minimize diesel consumption during power cuts? To answer these questions, have a look at this comprehensive guide EAI has published – the Diesel to Solar report, a comprehensive guide to implementing a rooftop solar system to reduce diesel consumption for power.

Related posts for replacing diesel with solar

Substituting Diesel with Rooftop Solar PV – Economics and Costs

Rooftop Solar – Solutions to Support Different Loads While Offsetting Diesel Consumption

Integrating Rooftop Solar with Diesel Generator for Diesel Reduction

Diesel Reduction Using Rooftop Solar Power – Constraints and Considerations

Replacing Diesel Gensets with Solar on Rooftops – Something Really Worth Exploring for Indian Industry

Also: Check out an interesting site on solar: Suncyclopedia, the Solar Encyclopedia

About Narasimhan Santhanam (Narsi)

Narsi, a Director at EAI, Co-founded one of India's first climate tech consulting firm in 2008.

Since then, he has assisted over 250 Indian and International firms, across many climate tech domain Solar, Bio-energy, Green hydrogen, E-Mobility, Green Chemicals.

Narsi works closely with senior and top management corporates and helps then devise strategy and go-to-market plans to benefit from the fast growing Indian Climate tech market.

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