I learnt today, that as from the end of February 2010, it will not be possible to obtain, or renew your European Health cards here  in Spain.
Instead you will need to apply to U.K. for them.

Hiya Ritaratbag-love your pen name!
I thought you could renew them online, so why the need to return to the Uk? They are putting all things online to reduce persona admin costs.

Moving to another country can be an overwhelming experience. Travel arrangements, accommodation and visa or work permission are obvious things to consider when preparing to move, but what about planning for your healthcare?

If you are moving to another European Economic Area (EEA) country or Switzerland on a permanent basis, you will also no longer be entitled to medical treatment under normal NHS rules.
Before leaving for your new destination, it's important to check what health services are available to you in that particular country. Healthcare systems vary from country to country and might not include services you would expect to get free of charge under the NHS. You should budget for any additional healthcare costs you may face, including health insurance.
However, you might be entitled to healthcare paid by the UK. This depends on whether you want to live abroad permanently, or only work outside the UK for a set period. The assistance available can also depend on whether or not you receive a UK state pension or other UK benefits.