I see this is an old question. But it needs an answer I think.
Inkscape supports saving as EPS by default - out of the box. However, things such as Inkscape patterns, transparency, and effects are not supported in EPS.
Only use EPS for output. Your original work should be saved as SVG which is Inkscape's native file format. This will preserve everything for future editing purposes.
PDF is a much better alternative to EPS for outputting documents from Inkscape, whether you want it to be or not.
If you want to open an EPS in Inkscape on Windows you need to install Ghostscript, and then you need to manually change your system path variables in Windows.
Comprehensive instructions appear on the Inskcape website FAQs. There's even a video tutorial on youtube if you need more guidance. I have tested these instructions and they work with the latest version of Inkscape 0.92.3, and Ghostscript 9.23 for Windows (64 bit).
If I can do it, anyone can. It doesn't take someone with a PHD to do it.
When you have done it. Restart Inskcape.
When you open an EPS, you get a dialog like this. It shows up as PDF Import Settings, because that is what Inkscape/Ghostscript is doing. It's converting the EPS (PostScript) to a PDF.
