The main obvious advantage of an HHO conversion is that you save on gas. Savings can be up to about 60%, although often the figure is nearer 30%. With Americans driving 40 billion less miles since the end of 2007 (from Department of Transportation figures), this whole technology is certainly capturing the interest of haulage firms as well as individuals.
Most governments have started to offer tax incentives for vehicle fuel conversions. In the USA, the IRS offers a $2,000 tax refund to anyone installing a kit. That shoots all the way up to $50,000 for a truck weighing over 26,000 lbs. In Australia they are debating the equivalent of over USD 5,000 for an average sedan. In any case, most places now you can spend around $200 and get at least $2,000 back before you even start saving on gas.
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