How about sending to genesis block account? Would that work?
http://elasticexplorer.org/address/XEL-H22F-GBXY-4BXS-6S4VQ/
There's a chance that someone has access to the genesis address. Not sure, though.
I tried finding out whether NXT-addresses (which XEL-adresses are based on) use checksums and I didn' find anything, so maybe you could "generate" burn addresses by choosing obviously non-random addresses, like XEL-BURN-ADDR-ESSX-XXXXX, XEL-XXXX-XXXX-XXXX-XXXXX and send the funds there. Not sure if this works, but since you want to burn them anyway, there's no harm in trying I guess. When making an address up, remember that NXT/XEL addresses don't use 0, O, I and 1.
I do not understand, I imagine that everyone will want to have more XEL, but someone wants to get rid of them?
There's a number of reasons, such as showing goodwill, getting rid of "tainted" (i.e. stolen) tokens which can't be returned for whatever reason etc.
Random fun fact: Counterparty used it as a means to distribute tokens to users. This is their burn address:
https://www.blockchain.com/btc/address/1CounterpartyXXXXXXXXXXXXXXXUWLpVr
(The last six random looking characters are the checksum I meant above)
So if I use the method you describe nobody will be able to claim those funds making them 100 % inaccessible, right?
Well, apart from the fact that there is no such thing as 100%, pretty much.
There are two widely recognized ways of "burning" coins, both include sending them to provably unspendable addresses. "Provably unspendable" means that the addresses themselves show that there is close to zero chance that anyone knows the associated private key by looking extremely deliberate. Basically, if someone is able to find the associated private key to a burn address, you can assume that they can find any key for any wallet on the chain.
I've pointed out the first method above.
The second method is not much different, but instead of the address itself, the public key is used. The public key is the key directly derived from the private key. Addresses are usually generated by taking a private key, performing cryptographic hashing on it to generate the public key. Then, cryptographic hashing is used on the public key to generate the address. XEL is no different in that regard. To generate a "burn address", you take a sufficiently non-random public key (all zeros is common) and generate an address out of it. This is a little more tricky and the address still looks random at first glance, which is why I'd prefer the first way.