Worked for one of the big six until recently.
There where many cheap tariffs last year and the year before which are now expiring.
Those tariffs where probably too cheap in the first place which is causing a double whammy of price increases as there have been multiple increases in price since then + the recent ofgem increase which is separate to the 2-3 increases a year directly from the energy companies.
Lots of people called who where on about 10-12p per unit (electric) and the cheapest now is somewhere in the neighbourhood of 18-20p. This is due to the previously mentioned multiple price increases from the suppliers and the recent ofgem increase.
Customers who on normal tariffs have seen an increase but not as big as some who have experienced a 50%+ increase. Had to deal with lots of customers claiming we are ripping them off and explain they have had VERY cheap energy comparative to other tariffs we offered and now that deal has ended.
The only thing you can do is see what renewal prices your company can offer you and compare it ageism's the companies who are generally much cheaper such as Octopus Energy, Avro Energy etc as they are probably going to be cheaper. In my case I switched from EDF who quoted 18.22p and Octopus gave me a fixed 1 year for 15.32.
You do have to keep in mind smaller companies are recently getting shutdown but one of the popular ones (Octopus) is just growing and growing.
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All the energy providers are as bad as each other, they all use exactly the same systems (SAP), don't have loyalty to ANY company.
Go with whichever companies gives you a FIXED unit rate for 1 or 2 years with no exit fee's and is the cheapest. Also get setup on whats called a Direct Debit Whole Amount Monthly, DO NOT do the Monthly fixed amount the whole amount means you get the direct debit discount and you just pay for EXACTLY your usage every month or every 3 months depending on what you choose. Its much more efficient and means your provider cant randomly wack up the monthly cost for no reason. The whole amount is not advertised anywhere, you have to call the company to get put onto it once you are with them, they do this because the company doesn't want you to do it as they can have YOUR MONEY sitting in there accounts making interest like they can with the monthly fixed and it looks better to the shareholders with all the money sitting there. However it by far the best way to pay your energy.
Switching is very easy nowadays through Uswitch, which usually gives you better prices than directly with the company and you can get cashback through Qudio/topcashback.
Prices are only going to go up, they are not going to go down, get fixed as soon as you can.
I guess you’d need to scale it up to one of the larger ~25kva (100A so comparable with a mains supply) diesel jobbies really. The type that the utility companies roll out whenever they do works.