Field test: PV Modules

A real world comparison between Mono, Poly, PERC and Dual PV Modules.

Total solar yield: --
Total solar yield: --
Total solar yield: --
Total solar yield: --
Total solar yield: --
Total solar yield: --
Installation date: 09-03-2020

* This is a field test and the results are specific for this installation on this location please research which is the best solution for your own situation as the results can be different based on environmental influences.

Total solar yield as of 27/03/2023 when the results were reset:
Mono: 9158 kWh
Split-cell: 9511 kWh
Poly: 9113 kWh
Perc: 9471 kWh
Perc-east: 1970 kWh
Perc-west: 1730 kWh

Sailing Uma: Off-grid energy usage

“If you want to travel the world, don’t buy a couch."

With 156,000 subscribers, the Sailing Uma YouTube channel is a fun and educational resource for voyaging sailors – particularly those on a budget that do their best to avoid marinas.

Doing so means living primarily off-grid using the power of the sun for Uma’s principal energy needs. No mean feat when you consider Uma has an electric motor for auxiliary propulsion, rather than diesel.


Uma is a 1972 Pearson 36. As her webpage says: “She is neither fancy and expensive, nor cheap and flimsy—to us, she is perfect. We wanted a name that carried with it the motivation and rational that led us to buy her in the first place. Her name was inspired by the Portuguese number 1 (uma), meaning first or primary.”

Dan & Kika

Dan & Kika are no ordinary couple and rather than explain their extraordinary achievements myself, you can gain some insight as to who they are and what makes them tick by checking out these links:

Electricity needs

Personally I’ve been following this adventurous couple ever since they first got Uma and started converting her to electric propulsion. My interest was to see how others do it, having converted in much the same way to auxiliary electric propulsion some 7 years ago myself – and having discovered just how hungry power needs onboard can be, when considering generation of electricity, storing the resulting energy and managing the use of that power.

My own electric journey with Sailing Yacht Elektra is linked from my personal webpage, along with a little about myself:

My own efforts aside, how have Dan & Kika done it?

Some of it is down to using efficient Victron Energy products, but that’s only part of the story. Good management of resources is also key. In this video Dan explains how they have arrived at a good balance and understanding of their energy needs.

Note: Do forgive Dan his muddling of Power (W) vs Energy (Wh), as you know what he means to say!


Having recently crossed the Atlantic to UK, Uma’s current stats say it all and give Dan & Kika the authority to talk about voyaging and energy use onboard a sailing yacht.

  • Countries Visited – 22
  • Nautical Miles Sailed – 18,358
  • Gallons of Diesel Consumed – 0

I trust you agree and enjoy the video above and their excellent YouTube channel.

My thanks to Dan & Kika for the use of images and content for this blog.

To learn more about energy onboard why not check out the Victron Energy booklet – Energy Unlimited, available for download as a PDF in our Whitepapers section of the main website.

John Rushworth


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