Cash savers have paid the highest price for the financial crisis. Interest rates are at a 300-year low, and look set to stay at this level for years to come.
If you are relying on a monthly income from cash savings, unfortunately, the future looks bleak. In the short term, a deposit account will provide a safe haven for your money but over the medium term, cash is almost guaranteed to lose you money due to inflation.
The best option would be for you to divide your £100,000 between that needed for the short term and that which you can lock away for the medium term. Each part can provide a monthly income.
The alternative to cash would be corporate bond funds, which provide an average monthly income that is 50% better than cash, and Global Equity Income funds, which provide twice the return of cash.
The risk with this is that your capital value, the £100,000, would be subject to the ups and downs of the stockmarket but the income on offer, together with the expectation of capital growth over the longer term, provide better prospects for you.
It would make sense to seek detailed financial recommendations from an independent financial adviser before investing to ensure a portfolio is constructed that meets your needs.