ElectraTherm commissioned 10 Power+ 4400s in Levice, Slovakia in June 2014. The Organic Rankine Cycle (ORC) systems were deployed on a centralized district heating system in Slovakia as a means of increasing on-site efficiency and generating clean energy.
ElectraTherm’s Power+ generates fuel-free, emission-free power from low temperature waste heat. The 10-machine installation utilizes the waste heat from two Rolls Royce gas turbines through a combined cycle. Exhaust from the turbines goes through a heat recovery steam generator, and lower temperature exhaust gas that cannot be utilized produces hot water to meet demand for heating on the municipality’s district heating system. The remaining heat runs through ElectraTherm’s Power+ Generators to generate clean energy and attain attractive feed-in-tariff incentives.
Hot water enters the Power+ between 77-122°C (170-252°F), where it heats a working fluid into pressurized vapor, using Organic Rankine Cycle (ORC) and proprietary technologies. As the vapor expands, it drives ElectraTherm’s patented twin screw power block, which spins an electric generator and produces emission free power. Run in parallel, the Power+ Generators in Levice generate approximately 500 kWe.
While combined cycle gas turbines are widely used throughout Europe for power generation and district heating, this is the first application of its kind to utilize ElectraTherm’s ORC technology for the lower temperature waste heat. The Power+ Generators help the site reach maximum efficiency levels through heat that would otherwise go to waste.