National Grid defended its dividend policy as it reported a solid first half, although profits fell seven per cent due to financing costs.Chief Executive Steve Holliday said the company needed to pay a half year dividend per share of 14.49p per share, matching last year's, to reward investors for underpinning plans to invest £26bn in its UK and US energy networks in the next eight years.There has been growing criticism of the UK's energy companies' decision to hike household bills while consumers are struggling with rising costs and stagnant or falling wages."Prices are only one of the things that need to be resolved to ensure we have reliable energy supplies," Holliday told the BBC."The funding to invest in networks comes from people who give us the equity and debt and they need to make a return and if we can't make that we can't invest."Holliday said the company had a solid start to the year and was on track for "good" full year results.Pre-tax profit fell 7% to £979m reflecting the temporary extra cost of pre-financing asset growth at attractive interest rates.The UK businesses started their first year under new regulatory price controls well, making good early progress and were on track to deliver strong returns for the year as a whole.National Grid said it was taking action in the US to improve internal processes and IT systems to support continued long-term profitable growth. National Grid added that it was keeping its forecast for operating performance, asset growth and earnings.The group plans capital spending of about £3.5bn in 2013/14, net of efficiency savings, expected to drive regulated asset growth of around 6%.PW