Jimmy Carter's first year in office may well do down in the history books as the Year of the Bite.

The two most important bills Carter has succeeded in pushing through Congress - the energy bill and the Social Security bill - both involve massive new federal taxes.

To be sure, the major impact of the two measures will not hit the economy until 1980 and 1981. And the bills are emerging from Congress in many ways substantially changed from the way the Carter administration first proposed them.

Nevertheless, if the measures pass in anywhere near the form expected. Americans could have to pay an estimated $56 billion in added taxes between now and the end of 1981 - most of it from 1980 on.

Moreover, despite some efforts to ease the impact, much of the new tax burden would be regressive - that is, hit lower-income taxpayers proportionally harder than the rich.

On energy, Carter has proposed what amounts to a series of sales taxes on fuel, designed to discourage consumption. On social Security, the proposals, among other things, would raise the tax rate on worker's wages.

What's more, the spate of new taxes would add significantly to inflation in the later years. In the case of the energy tax boost, the move would be deliberate: a primary prupose of the bill is to raise energy prices gradually to the level of would prices.

But the increase in Social Security payroll taxes also would add to the price spiral. As they do with other increases in labor costs, many businesses imply would pass the tax boost on to consumers in the form of higher prices.

Unless the administration can offset them the new tax increases will place a sizable drag on the economy in 1980 and 1981 by draining away what otherwise would be money that consumers could spend on purchases.

President Carter has promised he will enlarge his coming tax-cut proposals to take account of the Social Security tax rise. And much of the energy taxes may be rebated in some form or another. But economists say any real move to offset these tax boosts fully would be costly.

As a result, some economists say Carter has place himself in a box to avoid a serious slump three or four year from now, the President will have to cut taxes so sharply in 1980 and 1981 that there will be no room left in the budget for major new initiatives.

Otto Eckstein, a presidential economic adviser during the Johnson administration, says that, in effect. Carter's modest January to program proposals, such of the expected urban-financing plan the administration is considering, may be his last ones.

"There's no question that as far as his first term in office is concerned his fiscal initiatives will be over." Eckstein says. "For the next two years, it's really just going to be a holding action. Until the dust settles on these tax measures."

The situation may contain a bitter irony, because, in a large sense, it was the prospect of tax reductions - not increases - that Carter was counting on to fulfill his economic goals.

When the Georgian was running for President last year, he built his campaign on two basic pocketbook promises: the new administration would lower the tax burden and make it more equitable, and it would get the economy moving again.

It was the extra revenue from heightened economic growth that Carter was counting on to produce the surplus in the early 1980s that would balance the federal budget and finance new programs such as welfare overhaul and national health insurance.

At the same time, Carter was going to hold the tax burden to 21 per cent of the economy's total output. And he was going to overhaul the tax system to make it more progressive - that is, to scale the tax burden to ability to pay. ut now, Eckstein says, "that 21 per cent goal becomes simply impossible". And Rudolph G. Penner, a former Ford administration economist, says Carter will have to engineer major changes to achieve his goal of making the tax system more progressive.

To be sure, both tax increases were necessary. Without some increase in energy prices, analysts say, the nation would not be able to cut back on consumption. And the Social Security trust funds were well-known to be in need of repair.

And the timing of both packages was critical. Policitally, Carter virtually had to propose both during his first year in office in order to take advantage of his "honeymoon" momentum to get them through Congress. To attempt either in an election year would have been a disaster.

Still, despite the phase-ins, the impact will be substantial. And the measures serve to exacerbate recent trend in tax policy that is shifting the burden of the tax system away from the graduated income tax and more toward sales taxes and payroll taxes, both of which are less progressive.

The administration already has moved to blunt the adverse effects of some of the proposals. Carter proposed originally that Social Security costs be financed in part from the graduated income tax than from the more regressive payroll tax, as it now is.

He also asked Congress to raise the additional revenues by increasing the Social Security tax base - the amount of a worker's wages that is subject to tax - rather than the tax rate. The move would have shifted more of the burden to persons in higher wage brackets.

And finally, he proposed that the tax increases be phased in gradually, to minimize the impact, and be couple with companion boosts in Social Security benefits that would redistribute the money. (The benefits help make the tax boost less regressive: the lion's share will go to lower-income groups).

The administration took a similar tack in its energy tax package. The President proposed that much of the new tax boost be rebated to consumers, to prevent a drain on purchasing power. And the rebate plan was progressive, concentrating most of the refund on the poor.

Congress, however, has balked at some of these proposals. In the area of Social Security taxes. the bills now being considered by the conference committees would raise the tax rate as well as the wage base. And the Senate version would shift the burden more toward employers - scrapping the 50-50 split that has prevailed in the past.

On the energy bill, the Senate flatly refused to approve a rebate plan of any sort, voting instead to use the new revenues to finance tax "incentives" to the energy companies to increase production. The issue is one of the major bones of contention in the conference committee.

It's not entirely clear yet what the President will do to offset the impact of these new tax increases. Most analysts expect the administration will have to enlarge its 1978 tax cuts by several billion of dollars, over and above what it plans to propose to stimulate the economy.

But economists say Carter also will have to propose sizable tax cuts in 1979 and 1980 as well, to offset the major portions of the energy and Social Security tax boosts, scheduled to take effect in 1980 and 1981.

The administration already is under pressure from Republicans to cut income taxes by a massive 33 per cent across the board, which the GOP says is necessary to prevent the economy from going into a slump.

(Republicans have been charging all along that the Carter energy program was nothing more than a tax increase in disguise. The GOP proposed simply removing controls from energy prices - a move the Democrats say would allow the big oil companies to keep the extra profits).

Whatever the White House does, the solution is bound to be complicated. Both Republican and Democratic economists say it's going to be difficult to offset the tax boosts precisely: the tax cuts may not got to the same groups whose taxes have been raised. As a result, the tax cuts may not adequately offset the increases.

How the administration will cope with that impact remains to be seen. But Carter's first year in office is more likely to be remembered by its tax increases than by its progress on the economic font. And that means that for the President, 1980 - the date of the next election - could prove to be the Year of the Tiger.