Forge v1235
Mekanism v7.1.1.125
Buildcraft v6.1.8

Using a Heat Generator with Coal to output directly, or via Buildcraft kinesis pipes , to a Metallurgic Infuser produces a crash.

screenshots
Direct power: http://i.imgur.com/yvkr2oK.png
Buildcraft K.pipes: http://i.imgur.com/EolVNdr.png

crash logs
Direct power: http://pastebin.com/Z6FTBgh1
Buildcraft K.pipes: http://pastebin.com/TZ8NHj0V

Seems like it's a Thermal Expansion api related issue ("cofh/api/energy/IEnergyProvider"), and installing "CoFHCore-[1.7.10]3.0.0B8-36" does fix this issue.

It's because BC is shipping part of the cofh.api.energy package, but not all of it. I really wish people would stop doing that.

Installing CoFHLib should do the trick, and CoFHCore seems to have worked for you. I'll get onto BuildCraft to ship CoFHAPI|energy properly.

Thanks @unpairedbracket.