The Diesel vs. Renewables Trade-off Mix

rusted diesel sign                         Image result for sun wind clipart

Whether you are looking to go off-grid or deploy backup renewable power for your local generation facility, diesel is still important today and will be to a lesser  and declining extent moving forward for the next 5 to 10 years.

We at Harvistor have been  integrating Starwind5 with and their  division’s mobile power station to create a rapid depoly solution for off grid use which makes it easy to make the trade-offs and get the right mix solar, battery and diesel backup to your power generation and storage facility start’s generating a return in 5 to 7 years and, for extreme “hard to reach and service” locations,  reduces diesel fuel consumption quickly for a 3 year pay backup.

To understand the diesel and renewables trade-off , it’s first important to note that the trade-off is as much about generation types as it is storage types.

One look at the grid below helps explain.


Energy Type             Generation           Storage


Diesel                                      AC/DC                        Tank

Propane                                 AC/DC                         Bottle

Gas                                           AC/DC                        Pipeline


Solar                                        DC/AC/Heat              Batteries

Wind                                        DC/AC/Pressure      Batteries/Pressure Tank

Geothermal                           Heat/Pressure          Pipes/ Pressure Pipe or Tank

What’s the best mix for your “Behind the Fence” power generation facility or application?

Well in the end it’s site physical characteristic specific:

-Remote or Local?

-On or Off Grid?

On top of these considerations, project goals and objectives are also key:

  • Go Green to reduce Carbon Foot print
  • Lower Power Bill
  • Avoid Blackouts
  • Grow more Revenue

Making the Trade-offs to get the right mix: Not Easy…

The financial considerations for the life your power facility project also need to be addressed across Capex, install, O&M, regulatory , Tax and De-commissioning costs.

The short story in finding the right mix of diesel and renewables across different generation and storage types and capacities is that there is a lot of information to digest and the co-dependencies must be understand before any mix decisions can be made about the design of your power facility project.

Those installers and vendors left standing after the precipitous slide in solar pricing and the confusion around the government credit “beauty show” and which sites can actually support on-grid re-sale of power will tell you the long story version is more complicated to get the mix between diesel and renewables right given the goals of the project.

Then it’s also important to consider the multi-level government subsidies, credits, FITs “Feed in Tariffs” (for selling extra power back to the public grid) grants and loans.

Exhausted yet?  Add one more biggy…

Your power generation and storage facility needs to be BANKABLE.

BANKABLE PROJECTS:  Well Designed , Fast 5-7 year ROI

Bankable you say? What does that mean?

  • Will your vendors be around in 20 years?
  • Does the ROI and LCOE make sense?
  • Do you have enough capital? (20-30% is the norm)
  • Are you the first one they meet, or does the bank have experience?
  • Does the public grid have the local capacity to accept your power sales?
  • Does the PPA revenue received come from reliable sources?

Checking off “Yes” to the entire list above makes your project bankable.


Diesel (or their equivalent non renewable options) is an energy storage and generation type which must be included in all off-grid sites with reasonable road or rail access. Only those sites with really extreme remoteness with difficult access can really be considered a renewables only site.

Modularity of Design= Lower Carbon Foot Print and Lower Battery Costs

When designing you power facility and making those difficult diesel vs. renewable trade-offs to get the right mix of diesel vs. renewables, it’s important to keep your design modular, so as to age out battery banks as prices fall. This means running less capacity with deeper draw down (to say 20%) for shorter battery life of say 6-7 years versus only 50% draw down, to take advantage of new battery technology which will have 4X better price performance by then. Of course the designer needs to consider the cost of the upgrade and the timing of the upgrade as well as part of the cost equation.

How Much Solar vs. Wind Generation

Also to be considered is how much Solar vs. Wind generation., and how modular.  Solar Panel prices are about as low in price as they are going to get and will start to rise slowly in line with inflation, while small wind is expected to become cheaper and subsidies become more scarce. Starwind5 is ushering in a new Cost/W paradigm with 50% lower O&M costs and a much lower de-commissioning and disposal portion of the carbon foot print, which only now the bankers are catching on to when evaluating the total project costs as LCOE “Levelized Cost of Energy” Cradle to Grave.

How much Diesel? What a Question… For the Right Partner

What about Preventative Maintenance & Service Schedules? How Much fuel will you use? What will the price of Diesel be in 5 and then 10 years?

Like a three legged stool, Solar, Wind and Diesel Generation are co-dependent and Diesel operation hours will impact the depth of batteries used for both Solar and Wind. Sound simple to figure out? It’s not.

In the end experience, expertise and references are the difference when hiring an off-grid solution integrator, IF you are really focused on ROI and LCOE and getting a 5-7 year return on your capital and debt deployment to finance your power generation and storage facility “Behind the Fence”.

In the end it’s all about finding a partner with the right Experience, Expertise, References and Cutting Edge Diesel & Renewable Integration skills to make sure you hit that tough to get 5-7 ROI goal.

At Harvistor, we are confident we have found the right partner in and their solution. Together we are certain we will get it right with our local install and maintain partners to make sure their customers  go off-grid with that mix of diesel and renewables.