Columbia, SC (WLTX) - The American Health Care Act is now headed to the US Senate where they are expected to make changes to the House plan. But what is in the current one?

We caught up with Robert Hartwig, a risk management and insurance professor at USC to help explain it.

"What people are calling Trumpcare is going to be radically different from Obamacare," Hartwig said.

For starters, under Obamacare everyone had to have insurance or pay a penalty fee. With the new plan, having insurance is optional, but anyone who goes without insurance for more than two months would be charged an additional 30 percent in premiums for a year when they re-enter the insurance market.

"Where there's a danger is that probably 10-15 million people will probably elect to not buy coverage at all and those individuals will still get sick, they'll still get in accidents, and they'll have to pay for those costs out of their own pocket," Hartwig said.

Right now, insurance companies must provide 10 essential health benefits: pregnancy and maternal care, hospitalization, rehabilitation and habilitative services, ambulatory services, emergency services, mental health and substance use disorder services, laboratory services, pediatric services, preventive and wellness services, and prescription drugs. The new plan eliminates that requirement and gives the decision to the states.

"What that means is you'll be able to pick and choose different sorts of policies like you used to be able to before the Affordable Care Act, which could result in policies that cost less," Hartwig said.

Under Obamacare, subsidies were based on a person's income, with lower incomes receiving higher subsidies. Under the new plan, it would be based on age.

"We will see that people who utilize care more will wind up paying more," Hartwig said. "That could be the case whether you have a preexisting condition or if you are older."

The new proposal would give states the ability to "opt out" of covering pre-existing conditions. To address that, the House bill allocates $138 billion over the next 10 years to help states and insurers set up "high-risk pools".

Finally, where Obamacare expanded Medicaid coverage, the new plan would freeze it by 2020. Medicaid would have a spending cap, meaning the federal government would send states a fixed amount of money per Medicaid enrollee.

"So states ultimately are going to lose resources that they were able to use for providing healthcare to insurance to individuals, they're going to have to come up with a way to make the limited Medicaided dollars they have go further," Hartwig said.

Senate republicans could make more changes to the bill or take up an entirely different health care bill of their own. If they do that, it would have to then be reconciled with the House plan.