- Official Post
The way actual geothermal works is way too unrealistic for me, as it consumes lava (and it doesnt give any product like obsidian or cobblestone) to generate power.
normal generator should be able to consume lava as it consumes anything that a furnace does.
If you don't want to rework geothermal, you can use it as a part of the recipe of the new generator (Core Tap, in spoiler)
Geothermal generator rework \ New generator: (Idea of I don't now)
How Geothermal should work:
The Core Tap!
It uses the extreme heat of Minecraftia's planetary core to generate energy!
How it works:
You craft The Core Drill and place it. It should look similiar to the support scaffolding in the ICBM mod, but way larger. Then, you connect it to a High-Temperature Turbine using alloy pipes or insulated high-temperature pipes, depending on how deep you drill. After that, you have to insert high-temperature pipes/alloy pipes into The Core Drill. In less than 3 ingame months it reaches the inner core if you supply it with enough energy (512 EU/t). Of course, The Core Drillhead is so high-tech that it doesn't get damaged when digging down! But you don't get the energy yet! First, smelt tin ingots to create molten tin. Insert the molten tin into The Core Drill instead of the water used in today's geothermal power plants and your energy will flow out of your High-Temperature Turbine! Of course, when The Core Drill is currently drilling, it can't pump tin through the pipes, so no energy is generated.
The layers of Minecraftia:
The Outer Crust: It's the normal Minecraft underground world, accessed when The Core Drill drills down the first time. Here The Core Tap doesn't produce any energy, except when a piece of alloy pipe is submerged in lava(4EU/t). When The Core Drill drills through bedrock(it won't replace it, it will ignore it), it reaches...
The Inner Crust: Here some energy(8EU/t) is produced if alloy pipes are used. When The Core Drill reaches a depth of about 40 kilometers (after less than a day) it reaches...
The Upper Mantle: Here a medium amount(32EU/t) of electricity is produced, regardless of the pipe type used. But when 1000 km depth are reached (after less than 18 days), The Core Drill accesses...
The Lower Mantle: If The Core Drill reaches this layer, all alloy pipes in the whole system will melt and there's a 1 in 16 chance that there's a volcanic eruption if alloy pipes are used somewhere. From now on you will need high-temperature pipes. However, a large amount of energy(512EU/t) is generated when this layer is reached. For even more energy you need to reach 3000km depth(after less than 54 days), so "you" can access...
The Outer Core: Pretty large amounts of electricity(1024EU/t or more) can produced with the heat from the Outer Core, and it's the deepest safe layer. If you REALLY want energy, then you have to wait about three ingame months to reach 5000 km depth, because there is...
THE INNER CORE: Extreme energy(2048 EU/t or more Yes, more. I mean, look at how long it takes and how much it costs!). Extreme heat. Even high-temperature pipes can melt here! But from here you can get so much energy, SO MUCH ENERGY!!! OH MY IN MY OPINION NONEXISTANT GOD, IT'S SO MUCH ENERGY! Err, sorry.
Disasters:
Of course, such technologies don't come without risks. But if you don't access THE INNER CORE and if you don't use alloy pipes when you want to access the Lower Mantle (and deeper layers) you are safe. But if you do...
Pipe Melting
If you access the Lower Mantle with Alloy Pipes anywhere in your system or with a 1 in 7 chance every ingame day if you already accessed THE INNER CORE, some/all of your pipes will melt. If pipes melt, your Core Drill will tell you how many you have to replace in its GUI. You replace pipes by placing them into the pipe input slot of The Core Drill. But when a pipe melts, there is a 1 in 16 chance that there is a...
Volcanic eruption
Do you know the sonic explosive in the ICBM mod? Imagine the effect of 10 sonic explosives (not at the same time, but one after another, to increase the time of the eruption) that throw lava, burning rocks and fire blocks (so the whole area is set on fire) everywhere and leave behing a lava-filled crater. I made a few screenshots for the people who can't imagine that.
Display Spoiler
A volcano.
An eruption.
The same eruption, a few seconds later.
The Pipes
Alloy pipes are crafted out of advanced alloy, in the shape of a pipe. They are used until you reached the Lower Mantle. They are the only type of pipe that can generate energy in the Crust.( 
=Advanced Alloy) ... ... ...
This procuces a certain amount of sets of alloy pipes which can then be crafted into 64 alloy pipes.
High-temperature pipes are high-tech pipes made of carbon, because it has the highest melting point of al elements. Of course, you can't just use carbon plates. You have to fill your crafting grid with carbon mesh and surround the product combine the product with diamonds like so:
This then has to be compressed to get a piece of super carbon. This can then be used to create a certain amount of sets of high-temperature pipes.
... ... ...
One set can be crafted into 64 high-temperature pipes. Otherwise it would be way to expensive to get to The Inner Core, right?
Of course, if this woud come into contact with oxygen while tin flows through it, it would burst into flames. But there's a solution! Just coat the pipes in advanced alloy and they are fireproof and can be placed, for example in caves below your Core Drill! However, insulated pipes can't be put into The Core Drill.( 
=high-temperature pipe)
If you think it is too OP, reduce by 2 , 5 or 10 the energy it generates.
It could also have a new GUI that looks like a nuclear reactor GUI, and you "build" your drill.
(It comes with a basic design already prepared for people who doesnt want to make designs to generate energy)
changing items location affects drill stats : Drill Speed, Drill Energy usage, Drill Heat resistance, Energy Generation
Good designs makes it drill faster, use less energy, lower risk to melt
Bad designs makes it drill slower, use more energy , higher risk to melt
Some designs can melt pipes and even make it blow.
SpwnX's toughts
Actually i think this is going to be denied due opness or hightechness, or sent back to addons idea.
[legit in a server] (it would take 300 hours of gameplay lol)