The Energy Transformation of the Blue: From a Chaotic System to an Efficient Installation

Introduction

When we acquired the Sailing Blue, we were excited about embarking on a new adventure. However, we soon realized that our travel companion had some hidden issues. One of the most pressing was its energy system, which turned out to be a real challenge. In this article, we share how we found the electrical system of the boat, the problems we faced, and how we transformed it to make it safer, more efficient, and reliable.

The Original State: A Disorganized Electrical System

Upon inspecting the electrical system of the Blue after purchase, we discovered a tangle of wires that seemed like something out of a science fiction movie. The system consisted of two battery banks: one for service and another for the engine. Both used AGM batteries of 110 Ah, but here is where the problems began:

  • The service bank: This bank was made up of two batteries connected in parallel, but with a dangerous configuration. One battery was located near the engine, while the other was in the forward cabin, separated by about 5 meters. They were only connected via the positive pole using a 50 mm cable! This connection was not only inefficient but also potentially dangerous.
  • The engine bank: Although functional, the single battery dedicated to the engine already showed signs of wear.
  • Solar panels: There was a small solar panel installed on the stern arch, but it was disconnected and without an operational regulator. The available regulators were cheap and not in use.
  • Wind installation: On the engine, we found remnants of an old wind installation, but it was already unusable.
  • Shore power charger: There was a battery charger from 220V of good quality, though outdated and designed for three battery banks.

One of the most concerning aspects of the original system was the service bank, formed by two AGM batteries connected in parallel. This design may seem functional at first glance, but it hides serious problems:

  • Risks of connecting batteries in parallel: Although connecting batteries in parallel can increase total capacity, this practice has risks. Each battery has small differences in its state of charge, voltage, and internal resistance. When connected in parallel:

    • Batteries can exchange current between them, accelerating wear.
    • If one battery fails or discharges too much, it can damage the other due to voltage differences.
    • In our case, one battery was near the engine and the other in the forward cabin, separated by 5 meters. This distance exacerbated the problems, as the long wiring introduced significant voltage losses and increased overheating risks.

  • The danger with high loads: The anchor winch of the Blue consumed approximately 1000 W during short periods, generating very high current peaks. With the batteries connected in parallel and so far apart, the system was not only inefficient but also dangerous. The long and poorly sized cables could overheat excessively, increasing the risk of fire.

Another critical aspect we improved was the charging system from the engine's alternator. In the original system, a conventional diode separator was used to charge the battery banks. However, this type of separator has significant limitations:

  • Voltage drop in diodes: Traditional diodes introduce a significant voltage drop (approximately 0.7V per diode). This may seem small, but in a system where every volt counts, this loss significantly reduces charging efficiency.
  • Energy waste: Due to the voltage drop, part of the energy generated by the alternator does not reach the batteries, resulting in longer charging times and unnecessary wear on the alternator.

The Victron Argofet Technology: A Modern Solution

In our renovation, we replaced the conventional diode separator with a system based on Argofet technology from Victron. This advancement offers several key advantages:

  1. Minimal voltage drop: Unlike traditional diodes, Argofet devices have almost no voltage drop (less than 0.1V). This means practically all the energy generated by the alternator reaches the batteries, maximizing system efficiency.
  2. Faster charging: With fewer energy losses, the batteries charge more quickly during engine operation. This is especially useful for short trips or when engine use is limited.
  3. Advanced protection: The Argofet system includes overload, short-circuit, and extreme temperature protection functions, ensuring safe operation and extending the life of both the alternator and batteries.

By implementing this technology, we noticed a significant improvement in the energy efficiency of the Blue. We can now sail with greater confidence, knowing that our batteries are optimally charged even during brief periods of engine operation.

Our New Solar Panels

Another fundamental aspect we transformed was our solar capacity. Upon acquiring the Blue, we found a small disconnected solar panel on the stern arch, without an operational regulator. This was clearly insufficient for our needs. We decided to make a qualitative and quantitative leap:

  • New solar panels: We installed four 110W solar panels on the stern arch, providing a total power of 440W. With this system, even on moderately sunny days, we generate enough energy to cover nearly all our daily needs.
  • Victron MPPT Regulator: To efficiently manage solar energy, we incorporated a Victron MPPT regulator. This technology optimizes photovoltaic energy conversion, ensuring that every ray of sunlight is fully utilized.

With this renewed solar system, we've achieved greater energy independence. Under ideal conditions, the solar panels are capable of keeping our batteries fully charged without needing to rely on the engine or shore power.

Results and Lessons Learned

With the complete renovation of the energy system of the Blue, we've achieved a much safer and more reliable boat. Some key lessons we learned during this process:

  1. Avoiding long-distance parallel connections: This not only reduces efficiency but also increases failure and accident risks.
  2. Importance of quality components: Investing in modern equipment, such as smart chargers and solar regulators, makes a big difference in system durability and performance.
  3. Careful planning: Having a detailed electrical system plan before making changes is essential to identify problems and avoid errors.

Conclusions and Next Steps

The energy transformation of the Blue has been a rewarding project that taught us a lot about the importance of well-thought-out design. In a future article, we'll delve into the technical details of the current installation and share practical tips for improving onboard energy efficiency.

Of course, this is just an overview of the improvements made. In a future article, we'll fully detail our current installation, including:

  • The Victron inverter that converts direct current to alternating current to power 220V devices.
  • The monitoring shunt that allows us to track energy consumption and production in real-time.
  • Other key equipment that makes the Blue an example of energy efficiency.