<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>labcomputer</author><text>You have to do some “energy accounting” sleight of hand to get 63%, though. That number assumes that some of the low-grade waste heat can be used for, e.g., district heating. It’s also a peak steady-state number, only achievable under optimal load conditions.</text><parent_chain><item><author>londons_explore</author><text>&amp;gt; emitter temperature of 2,400 C&lt;p&gt;GE&amp;#x27;s combined cycle turbines can get system level efficiency of around 63% from these sorts of temperatures.&lt;p&gt;(For those not familiar with them: They&amp;#x27;re basically aircraft jet engines followed by steam turbines using the hot exhaust.  They are in widespread use to generate electricity from gas, but they can also run off any other liquid fuel, or simply off anything that gets very hot.)</text></item></parent_chain></comment><story><title>US startup begins producing 40%-efficient thermophotovoltaic cells</title><url>https://www.pv-magazine.com/2023/01/25/us-startup-begins-producing-40-efficient-thermophotovoltaic-cells/</url></story>
<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>15457345234</author><text>There are a looooot of moving parts in a CCGT generating station, multiple oil loops, multiple coolant loops, many consumables, a complex control flow.&lt;p&gt;Being able to replace the combined turbine&amp;#x2F;alternator assembly with a &amp;#x27;when it gets hot, voltage comes out&amp;#x27; unit would give you significant reliability gains and lower operating costs.</text><parent_chain><item><author>londons_explore</author><text>&amp;gt; emitter temperature of 2,400 C&lt;p&gt;GE&amp;#x27;s combined cycle turbines can get system level efficiency of around 63% from these sorts of temperatures.&lt;p&gt;(For those not familiar with them: They&amp;#x27;re basically aircraft jet engines followed by steam turbines using the hot exhaust.  They are in widespread use to generate electricity from gas, but they can also run off any other liquid fuel, or simply off anything that gets very hot.)</text></item></parent_chain></comment><story><title>US startup begins producing 40%-efficient thermophotovoltaic cells</title><url>https://www.pv-magazine.com/2023/01/25/us-startup-begins-producing-40-efficient-thermophotovoltaic-cells/</url></story>