For operators responsible for remote sites, cathodic protection systems, SCADA infrastructure, or hybrid power packages, the first priority is usually not what technology is newest. It’s what will run reliably and safely in the field.
Thermoelectric generators (TEGs) play a practical role in low-power remote applications. Understanding what a TEG is, where it fits, how to size one properly, and what operators can realistically expect from one is worth the time if you’re evaluating remote power options.
What a TEG does
TEGs are solid-state systems with no moving parts. They convert heat from combusting fuel, typically natural gas or propane, into DC power. The process is mechanically simple. Fuel enters the burner, heat is generated, and the temperature difference between the hot and cool sides of the thermopile produces DC power. Ambient air is drawn through the cooling fins, and rejected heat exits through the duct system. The simplicity of the system is the major reason they deliver long service life with relatively low maintenance.In fact, Global Power Technologies often hears of units that have been in service for over 30 years. While a 20-year design life is standard, and some systems have operated much longer.
Where TEGs fit best
TEGs cover low-power generation, depending on the model they generate between 5 watts to 550 watts per unit, and multiple units can be run in parallel when higher output is required.
Hazardous-location models are available for environments where spacing is limited and equipment needs to operate safely in hazardous locations like offshore platforms or near wellheads and process tanks. Some models also include flame-arrestors to reduce spacing requirements of general area TEGs which lowers install costs.
Two common applications are powering impressed current cathodic protection and SCADA equipment on sites with limited or no grid access. In those settings, native DC output becomes a clear advantage. For cathodic protection specifically, a CP-TEG includes an integrated CP panel which removes the need for a separate rectifier that grid-based AC power would require.
TEGs also work well in solar hybrid systems. In colder regions or lower-irradiance seasons, a TEG improves battery performance and reduces deep discharge frequency. That matters because battery replacement, site visits, theft, and downtime often cost more than operators expect at the start of a project.
Combined heat and power is another fit. In suitable installations, rejected heat can warm a building while the unit continues providing steady power.
Offshore and marine-rated applications are also relevant, particularly for uncrewed platforms where durability, compactness, and hazardous-location suitability are critical.
Why sizing matters
When sizing a TEG, the most important considerations are the site’s peak load and its continuous load. The goal is not to oversize the unit to cover every short-duration peak. Batteries handle those peaks while the TEG is sized to support continuous demand efficiently.
Environmental and site-specific constraints affect output too. High ambient temperatures and high-altitude locations reduce cooling performance, which reduces available power. For solar hybrid applications, the TEG must be sized appropriately to avoid excessive cycling which can degrade the power unit faster than intended. GPT’s simulation tools can evaluate solar resources over the year and recommend an appropriately sized TEG.
Product selection is never just about wattage.
What field examples show
In one southern U.S. example, an operator relying on solar-only systems in Texas and Oklahoma was facing major battery replacement and theft-related costs, reportedly up to $1.2 million per year. After converting those sites to TEG solar hybrids, the operator reduced outages and recovered capital costs through lower site-visit and battery-replacement expenses.
In Italy, SCADA systems powered only by solar and wind needed less than 100 watts. Adding a P5050 TEG to support the existing battery system eliminated repeated site visits and supported a zero-interruption service expectation.
The clearest illustration of product life: a unit commissioned in 1987 near Drayton Valley for cathodic protection service. After decades of operation, a power unit replacement in 1996, and refurbishment in 2017, the system was returned to the field and continues to run. While we would not suggest every installation follows that timeline, it illustrates the durability these systems can deliver.
What to evaluate next
A TEG is the right answer when the application calls for long-life, low-maintenance DC power at remote sites where reliability, site access, and total operating cost matter more than theoretical simplicity on paper.
TEGs provide native DC output, useful for cathodic protection and other low-power applications. They’re solid-state with no moving parts, which supports long service life and simple maintenance. They strengthen battery-backed and solar hybrid systems where downtime, theft, or harsh seasonal conditions create operating risk. Proper sizing and site evaluation will ensure the system performs as intended.
If you’re evaluating remote power, talk to Global Power Technologies about sizing a TEG or TEG-solar hybrid for your site. A review of your continuous load, peak demand, and site conditions will help determine the most practical configuration before you commit to equipment.