It's a mistake to assume that your car insurance automatically covers you to drive to and from work. In order to use your car in this way your policy must cover you for commuting purposes. This is often referred to as social, domestic, pleasure and commuting cover.
Additionally, commuting cover will only allow you to drive to/from your usual place of work. If you use your vehicle to go to a meeting, conference or seminar etc. whilst at work you will require business cover.
If you are unsure whether your car insurance includes this, you will need to check your insurance certificate and policy documents. Then, if you are still uncertain, contact your insurer and clarify the matter with them.
If you are stopped by the police and they have reasonable grounds to believe your insurance isn't valid, they can seize your car and you can be prosecuted. The penalty for using a vehicle without insurance is a £300 fixed penalty and 6 penalty points or if the matter goes to court, an unlimited fine and 6 to 8 penalty points.